Proposed resolution:
This wording is relative to N4562.
Edit [optional.optional]/p1 as follows::
[…] The contained value shall be allocated in a region of the optional<T> storage suitably aligned for the type T. It is implementation-defined whether over-aligned types are supported (C++14 §3.11). When an object of type optional<T> is contextually converted to bool, the conversion returns true if the object contains a value; otherwise the conversion returns false.