Proposed resolution:

This wording is relative to N4567.

1. Edit [map.modifiers] as indicated:

   template <class P> pair<iterator, bool> insert(P&& x);
   template <class P> iterator insert(const_iterator position, P&& x);
   template <class InputIterator>
   void insert(InputIterator first, InputIterator last);
   

   -1- Effects: The first form is equivalent to return emplace(std::forward<P>(x)). The second form is equivalent to return emplace_hint(position, std::forward<P>(x)).

   -2- Remarks: These signatures shall not participate in overload resolution unless std::is_constructible<value_type, P&&>::value is true.