Rationale:

Just a typo, this is really editorial.

Proposed resolution:

Replace "((T*) p)" with "p".

[allocator.members] allocator members, contains the following 3 lines:

  12 Returns: new((void *) p) T( val)
     void destroy(pointer p);
  13 Returns: ((T*) p)->~T()

The type cast "(T*) p" in the last line is redundant cause we know that std::allocator<T>::pointer is a typedef for T*.