diff --git a/include/pybind11/smart_holder_poc.h b/include/pybind11/smart_holder_poc.h
index 5a30b7796..4d14409cf 100644
--- a/include/pybind11/smart_holder_poc.h
+++ b/include/pybind11/smart_holder_poc.h
@@ -75,16 +75,6 @@ struct smart_holder {
   bool vptr_is_using_builtin_delete : 1;
   bool vptr_is_external_shared_ptr : 1;
 
-  void clear() {
-    rtti_held = nullptr;
-    rtti_uqp_del = nullptr;
-    vptr.reset();
-    vptr_deleter_guard_flag = false;
-    vptr_is_using_noop_deleter = false;
-    vptr_is_using_builtin_delete = false;
-    vptr_is_external_shared_ptr = false;
-  }
-
   smart_holder()
       : rtti_held{nullptr},
         rtti_uqp_del{nullptr},
@@ -151,11 +141,13 @@ struct smart_holder {
   }
 
   template <typename T>
-  void from_raw_ptr_unowned(T* raw_ptr) {
-    clear();
-    rtti_held = &typeid(T);
-    vptr_is_using_noop_deleter = true;
-    vptr.reset(raw_ptr, guarded_builtin_delete<T>(&vptr_deleter_guard_flag));
+  static smart_holder from_raw_ptr_unowned(T* raw_ptr) {
+    smart_holder hld;
+    hld.rtti_held = &typeid(T);
+    hld.vptr_is_using_noop_deleter = true;
+    hld.vptr.reset(raw_ptr,
+                   guarded_builtin_delete<T>(&hld.vptr_deleter_guard_flag));
+    return hld;
   }
 
   template <typename T>
@@ -174,12 +166,14 @@ struct smart_holder {
   }
 
   template <typename T>
-  void from_raw_ptr_take_ownership(T* raw_ptr) {
-    clear();
-    rtti_held = &typeid(T);
-    vptr_deleter_guard_flag = true;
-    vptr_is_using_builtin_delete = true;
-    vptr.reset(raw_ptr, guarded_builtin_delete<T>(&vptr_deleter_guard_flag));
+  static smart_holder from_raw_ptr_take_ownership(T* raw_ptr) {
+    smart_holder hld;
+    hld.rtti_held = &typeid(T);
+    hld.vptr_deleter_guard_flag = true;
+    hld.vptr_is_using_builtin_delete = true;
+    hld.vptr.reset(raw_ptr,
+                   guarded_builtin_delete<T>(&hld.vptr_deleter_guard_flag));
+    return hld;
   }
 
   template <typename T>
@@ -195,14 +189,15 @@ struct smart_holder {
   }
 
   template <typename T>
-  void from_unique_ptr(std::unique_ptr<T>&& unq_ptr) {
-    clear();
-    rtti_held = &typeid(T);
-    vptr_deleter_guard_flag = true;
-    vptr_is_using_builtin_delete = true;
-    vptr.reset(unq_ptr.get(),
-               guarded_builtin_delete<T>(&vptr_deleter_guard_flag));
+  static smart_holder from_unique_ptr(std::unique_ptr<T>&& unq_ptr) {
+    smart_holder hld;
+    hld.rtti_held = &typeid(T);
+    hld.vptr_deleter_guard_flag = true;
+    hld.vptr_is_using_builtin_delete = true;
+    hld.vptr.reset(unq_ptr.get(),
+                   guarded_builtin_delete<T>(&hld.vptr_deleter_guard_flag));
     unq_ptr.release();
+    return hld;
   }
 
   template <typename T>
@@ -211,14 +206,16 @@ struct smart_holder {
   }
 
   template <typename T, typename D>
-  void from_unique_ptr_with_deleter(std::unique_ptr<T, D>&& unq_ptr) {
-    clear();
-    rtti_held = &typeid(T);
-    rtti_uqp_del = &typeid(D);
-    vptr_deleter_guard_flag = true;
-    vptr.reset(unq_ptr.get(),
-               guarded_custom_deleter<T, D>(&vptr_deleter_guard_flag));
+  static smart_holder from_unique_ptr_with_deleter(
+      std::unique_ptr<T, D>&& unq_ptr) {
+    smart_holder hld;
+    hld.rtti_held = &typeid(T);
+    hld.rtti_uqp_del = &typeid(D);
+    hld.vptr_deleter_guard_flag = true;
+    hld.vptr.reset(unq_ptr.get(),
+                   guarded_custom_deleter<T, D>(&hld.vptr_deleter_guard_flag));
     unq_ptr.release();
+    return hld;
   }
 
   template <typename T, typename D>
@@ -234,11 +231,12 @@ struct smart_holder {
   }
 
   template <typename T>
-  void from_shared_ptr(std::shared_ptr<T> shd_ptr) {
-    clear();
-    rtti_held = &typeid(T);
-    vptr_is_external_shared_ptr = true;
-    vptr = std::static_pointer_cast<void>(shd_ptr);
+  static smart_holder from_shared_ptr(std::shared_ptr<T> shd_ptr) {
+    smart_holder hld;
+    hld.rtti_held = &typeid(T);
+    hld.vptr_is_external_shared_ptr = true;
+    hld.vptr = std::static_pointer_cast<void>(shd_ptr);
+    return hld;
   }
 
   template <typename T>
diff --git a/tests/core/smart_holder_poc_test.cpp b/tests/core/smart_holder_poc_test.cpp
index e014757a9..9aebba62f 100644
--- a/tests/core/smart_holder_poc_test.cpp
+++ b/tests/core/smart_holder_poc_test.cpp
@@ -19,22 +19,19 @@ struct functor_other_delete : functor_builtin_delete<T> {};
 
 TEST_CASE("from_raw_ptr_unowned+as_raw_ptr_unowned", "[S]") {
   static int value = 19;
-  smart_holder hld;
-  hld.from_raw_ptr_unowned(&value);
+  auto hld = smart_holder::from_raw_ptr_unowned(&value);
   REQUIRE(*hld.as_raw_ptr_unowned<int>() == 19);
 }
 
 TEST_CASE("from_raw_ptr_unowned+const_value_ref", "[S]") {
   static int value = 19;
-  smart_holder hld;
-  hld.from_raw_ptr_unowned(&value);
+  auto hld = smart_holder::from_raw_ptr_unowned(&value);
   REQUIRE(hld.const_value_ref<int>() == 19);
 }
 
 TEST_CASE("from_raw_ptr_unowned+as_raw_ptr_release_ownership", "[E]") {
   static int value = 19;
-  smart_holder hld;
-  hld.from_raw_ptr_unowned(&value);
+  auto hld = smart_holder::from_raw_ptr_unowned(&value);
   REQUIRE_THROWS_WITH(
       hld.as_raw_ptr_release_ownership<int>(),
       "Cannot disown non-owning holder (as_raw_ptr_release_ownership).");
@@ -42,16 +39,14 @@ TEST_CASE("from_raw_ptr_unowned+as_raw_ptr_release_ownership", "[E]") {
 
 TEST_CASE("from_raw_ptr_unowned+as_unique_ptr", "[E]") {
   static int value = 19;
-  smart_holder hld;
-  hld.from_raw_ptr_unowned(&value);
+  auto hld = smart_holder::from_raw_ptr_unowned(&value);
   REQUIRE_THROWS_WITH(hld.as_unique_ptr<int>(),
                       "Cannot disown non-owning holder (as_unique_ptr).");
 }
 
 TEST_CASE("from_raw_ptr_unowned+as_unique_ptr_with_deleter", "[E]") {
   static int value = 19;
-  smart_holder hld;
-  hld.from_raw_ptr_unowned(&value);
+  auto hld = smart_holder::from_raw_ptr_unowned(&value);
   auto condense_for_macro = [](smart_holder& hld) {
     hld.as_unique_ptr_with_deleter<int, helpers::functor_builtin_delete<int>>();
   };
@@ -62,21 +57,18 @@ TEST_CASE("from_raw_ptr_unowned+as_unique_ptr_with_deleter", "[E]") {
 
 TEST_CASE("from_raw_ptr_unowned+as_shared_ptr", "[S]") {
   static int value = 19;
-  smart_holder hld;
-  hld.from_raw_ptr_unowned(&value);
+  auto hld = smart_holder::from_raw_ptr_unowned(&value);
   REQUIRE(*hld.as_shared_ptr<int>() == 19);
 }
 
 TEST_CASE("from_raw_ptr_take_ownership+const_value_ref", "[S]") {
-  smart_holder hld;
-  hld.from_raw_ptr_take_ownership(new int(19));
+  auto hld = smart_holder::from_raw_ptr_take_ownership(new int(19));
   REQUIRE(hld.has_pointee());
   REQUIRE(hld.const_value_ref<int>() == 19);
 }
 
 TEST_CASE("from_raw_ptr_take_ownership+as_raw_ptr_release_ownership1", "[S]") {
-  smart_holder hld;
-  hld.from_raw_ptr_take_ownership(new int(19));
+  auto hld = smart_holder::from_raw_ptr_take_ownership(new int(19));
   auto new_owner =
       std::unique_ptr<int>(hld.as_raw_ptr_release_ownership<int>());
   REQUIRE(!hld.has_pointee());
@@ -84,8 +76,7 @@ TEST_CASE("from_raw_ptr_take_ownership+as_raw_ptr_release_ownership1", "[S]") {
 }
 
 TEST_CASE("from_raw_ptr_take_ownership+as_raw_ptr_release_ownership2", "[E]") {
-  smart_holder hld;
-  hld.from_raw_ptr_take_ownership(new int(19));
+  auto hld = smart_holder::from_raw_ptr_take_ownership(new int(19));
   auto shd_ptr = hld.as_shared_ptr<int>();
   REQUIRE_THROWS_WITH(
       hld.as_raw_ptr_release_ownership<int>(),
@@ -93,24 +84,21 @@ TEST_CASE("from_raw_ptr_take_ownership+as_raw_ptr_release_ownership2", "[E]") {
 }
 
 TEST_CASE("from_raw_ptr_take_ownership+as_unique_ptr1", "[S]") {
-  smart_holder hld;
-  hld.from_raw_ptr_take_ownership(new int(19));
+  auto hld = smart_holder::from_raw_ptr_take_ownership(new int(19));
   std::unique_ptr<int> new_owner = hld.as_unique_ptr<int>();
   REQUIRE(!hld.has_pointee());
   REQUIRE(*new_owner == 19);
 }
 
 TEST_CASE("from_raw_ptr_take_ownership+as_unique_ptr2", "[E]") {
-  smart_holder hld;
-  hld.from_raw_ptr_take_ownership(new int(19));
+  auto hld = smart_holder::from_raw_ptr_take_ownership(new int(19));
   auto shd_ptr = hld.as_shared_ptr<int>();
   REQUIRE_THROWS_WITH(hld.as_unique_ptr<int>(),
                       "Cannot disown use_count != 1 (as_unique_ptr).");
 }
 
 TEST_CASE("from_raw_ptr_take_ownership+as_unique_ptr_with_deleter", "[E]") {
-  smart_holder hld;
-  hld.from_raw_ptr_take_ownership(new int(19));
+  auto hld = smart_holder::from_raw_ptr_take_ownership(new int(19));
   auto condense_for_macro = [](smart_holder& hld) {
     hld.as_unique_ptr_with_deleter<int, helpers::functor_builtin_delete<int>>();
   };
@@ -120,8 +108,7 @@ TEST_CASE("from_raw_ptr_take_ownership+as_unique_ptr_with_deleter", "[E]") {
 }
 
 TEST_CASE("from_raw_ptr_take_ownership+as_shared_ptr", "[S]") {
-  smart_holder hld;
-  hld.from_raw_ptr_take_ownership(new int(19));
+  auto hld = smart_holder::from_raw_ptr_take_ownership(new int(19));
   std::shared_ptr<int> new_owner = hld.as_shared_ptr<int>();
   REQUIRE(hld.has_pointee());
   REQUIRE(*new_owner == 19);
@@ -129,16 +116,14 @@ TEST_CASE("from_raw_ptr_take_ownership+as_shared_ptr", "[S]") {
 
 TEST_CASE("from_unique_ptr+const_value_ref", "[S]") {
   std::unique_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   REQUIRE(hld.const_value_ref<int>() == 19);
 }
 
 TEST_CASE("from_unique_ptr+as_raw_ptr_release_ownership1", "[S]") {
   std::unique_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   auto new_owner =
       std::unique_ptr<int>(hld.as_raw_ptr_release_ownership<int>());
@@ -148,8 +133,7 @@ TEST_CASE("from_unique_ptr+as_raw_ptr_release_ownership1", "[S]") {
 
 TEST_CASE("from_unique_ptr+as_raw_ptr_release_ownership2", "[E]") {
   std::unique_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   auto shd_ptr = hld.as_shared_ptr<int>();
   REQUIRE_THROWS_WITH(
@@ -159,8 +143,7 @@ TEST_CASE("from_unique_ptr+as_raw_ptr_release_ownership2", "[E]") {
 
 TEST_CASE("from_unique_ptr+as_unique_ptr1", "[S]") {
   std::unique_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   std::unique_ptr<int> new_owner = hld.as_unique_ptr<int>();
   REQUIRE(!hld.has_pointee());
@@ -169,8 +152,7 @@ TEST_CASE("from_unique_ptr+as_unique_ptr1", "[S]") {
 
 TEST_CASE("from_unique_ptr+as_unique_ptr2", "[E]") {
   std::unique_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   auto shd_ptr = hld.as_shared_ptr<int>();
   REQUIRE_THROWS_WITH(hld.as_unique_ptr<int>(),
@@ -179,8 +161,7 @@ TEST_CASE("from_unique_ptr+as_unique_ptr2", "[E]") {
 
 TEST_CASE("from_unique_ptr+as_unique_ptr_with_deleter", "[E]") {
   std::unique_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   auto condense_for_macro = [](smart_holder& hld) {
     hld.as_unique_ptr_with_deleter<int, helpers::functor_builtin_delete<int>>();
@@ -192,8 +173,7 @@ TEST_CASE("from_unique_ptr+as_unique_ptr_with_deleter", "[E]") {
 
 TEST_CASE("from_unique_ptr+as_shared_ptr", "[S]") {
   std::unique_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   std::shared_ptr<int> new_owner = hld.as_shared_ptr<int>();
   REQUIRE(hld.has_pointee());
@@ -203,8 +183,7 @@ TEST_CASE("from_unique_ptr+as_shared_ptr", "[S]") {
 TEST_CASE("from_unique_ptr_with_deleter+const_value_ref", "[S]") {
   std::unique_ptr<int, helpers::functor_builtin_delete<int>> orig_owner(
       new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr_with_deleter(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr_with_deleter(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   REQUIRE(hld.const_value_ref<int>() == 19);
 }
@@ -212,8 +191,7 @@ TEST_CASE("from_unique_ptr_with_deleter+const_value_ref", "[S]") {
 TEST_CASE("from_unique_ptr_with_deleter+as_raw_ptr_release_ownership", "[E]") {
   std::unique_ptr<int, helpers::functor_builtin_delete<int>> orig_owner(
       new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr_with_deleter(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr_with_deleter(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   REQUIRE_THROWS_WITH(
       hld.as_raw_ptr_release_ownership<int>(),
@@ -223,8 +201,7 @@ TEST_CASE("from_unique_ptr_with_deleter+as_raw_ptr_release_ownership", "[E]") {
 TEST_CASE("from_unique_ptr_with_deleter+as_unique_ptr", "[E]") {
   std::unique_ptr<int, helpers::functor_builtin_delete<int>> orig_owner(
       new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr_with_deleter(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr_with_deleter(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   REQUIRE_THROWS_WITH(hld.as_unique_ptr<int>(),
                       "Cannot disown custom deleter (as_unique_ptr).");
@@ -233,8 +210,7 @@ TEST_CASE("from_unique_ptr_with_deleter+as_unique_ptr", "[E]") {
 TEST_CASE("from_unique_ptr_with_deleter+as_unique_ptr_with_deleter1", "[S]") {
   std::unique_ptr<int, helpers::functor_builtin_delete<int>> orig_owner(
       new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr_with_deleter(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr_with_deleter(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   std::unique_ptr<int, helpers::functor_builtin_delete<int>> new_owner =
       hld.as_unique_ptr_with_deleter<int,
@@ -246,8 +222,7 @@ TEST_CASE("from_unique_ptr_with_deleter+as_unique_ptr_with_deleter1", "[S]") {
 TEST_CASE("from_unique_ptr_with_deleter+as_unique_ptr_with_deleter2", "[E]") {
   std::unique_ptr<int, helpers::functor_builtin_delete<int>> orig_owner(
       new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr_with_deleter(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr_with_deleter(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   auto condense_for_macro = [](smart_holder& hld) {
     hld.as_unique_ptr_with_deleter<int, helpers::functor_other_delete<int>>();
@@ -260,8 +235,7 @@ TEST_CASE("from_unique_ptr_with_deleter+as_unique_ptr_with_deleter2", "[E]") {
 TEST_CASE("from_unique_ptr_with_deleter+as_shared_ptr", "[S]") {
   std::unique_ptr<int, helpers::functor_builtin_delete<int>> orig_owner(
       new int(19));
-  smart_holder hld;
-  hld.from_unique_ptr_with_deleter(std::move(orig_owner));
+  auto hld = smart_holder::from_unique_ptr_with_deleter(std::move(orig_owner));
   REQUIRE(orig_owner.get() == nullptr);
   std::shared_ptr<int> new_owner = hld.as_shared_ptr<int>();
   REQUIRE(hld.has_pointee());
@@ -270,15 +244,13 @@ TEST_CASE("from_unique_ptr_with_deleter+as_shared_ptr", "[S]") {
 
 TEST_CASE("from_shared_ptr+const_value_ref", "[S]") {
   std::shared_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_shared_ptr(orig_owner);
+  auto hld = smart_holder::from_shared_ptr(orig_owner);
   REQUIRE(hld.const_value_ref<int>() == 19);
 }
 
 TEST_CASE("from_shared_ptr+as_raw_ptr_release_ownership", "[E]") {
   std::shared_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_shared_ptr(orig_owner);
+  auto hld = smart_holder::from_shared_ptr(orig_owner);
   REQUIRE_THROWS_WITH(
       hld.as_raw_ptr_release_ownership<int>(),
       "Cannot disown external shared_ptr (as_raw_ptr_release_ownership).");
@@ -286,16 +258,14 @@ TEST_CASE("from_shared_ptr+as_raw_ptr_release_ownership", "[E]") {
 
 TEST_CASE("from_shared_ptr+as_unique_ptr", "[E]") {
   std::shared_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_shared_ptr(orig_owner);
+  auto hld = smart_holder::from_shared_ptr(orig_owner);
   REQUIRE_THROWS_WITH(hld.as_unique_ptr<int>(),
                       "Cannot disown external shared_ptr (as_unique_ptr).");
 }
 
 TEST_CASE("from_shared_ptr+as_unique_ptr_with_deleter", "[E]") {
   std::shared_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_shared_ptr(orig_owner);
+  auto hld = smart_holder::from_shared_ptr(orig_owner);
   auto condense_for_macro = [](smart_holder& hld) {
     hld.as_unique_ptr_with_deleter<int, helpers::functor_builtin_delete<int>>();
   };
@@ -306,8 +276,7 @@ TEST_CASE("from_shared_ptr+as_unique_ptr_with_deleter", "[E]") {
 
 TEST_CASE("from_shared_ptr+as_shared_ptr", "[S]") {
   std::shared_ptr<int> orig_owner(new int(19));
-  smart_holder hld;
-  hld.from_shared_ptr(orig_owner);
+  auto hld = smart_holder::from_shared_ptr(orig_owner);
   REQUIRE(*hld.as_shared_ptr<int>() == 19);
 }
 
@@ -319,15 +288,13 @@ TEST_CASE("error_unpopulated_holder", "[E]") {
 
 TEST_CASE("error_incompatible_type", "[E]") {
   static int value = 19;
-  smart_holder hld;
-  hld.from_raw_ptr_unowned(&value);
+  auto hld = smart_holder::from_raw_ptr_unowned(&value);
   REQUIRE_THROWS_WITH(hld.as_unique_ptr<std::string>(),
                       "Incompatible type (as_unique_ptr).");
 }
 
 TEST_CASE("error_disowned_holder", "[E]") {
-  smart_holder hld;
-  hld.from_raw_ptr_take_ownership(new int(19));
+  auto hld = smart_holder::from_raw_ptr_take_ownership(new int(19));
   hld.as_unique_ptr<int>();
   REQUIRE_THROWS_WITH(hld.const_value_ref<int>(),
                       "Disowned holder (const_value_ref).");