Where's your point of confusion? There's still virtual dispatch going on with a pointer to virtual member function... they're typically implemented as fat poin

Where's your point of confusion? There's still virtual dispatch going on with a pointer to virtual member function... they're typically implemented as fat pointers containing the vtable offset, and calling via the pointer still does virtual dispatch. An alternative would be for the compiler to generate a stub function (can be shared across all classes for cases where the same vtable offset is used, unless your architecture has some very exotic calling convention) that jumps to a fixed offset in the vitable, and use a skinny pointer to that stub as a virtual member function pointer, but that's not the usual implementation. In any case, calling through a pointer to virtual member function has to perform virtual dispatch unless the compiler can statically constrain the runtime type of *this being used at the call site. Remember that C++ needs to allow separate compilation, so without a full-program optimizer that breaks dlopen(), C++ can't perform devirtualization on non-final classes. Making the class final will allow the compiler to statically constrain the runtime type and devirtualize the pointer to member function call. Edit: added paragraph break.