The unix model should be followed (requiring an explicit reference to the current directory if it is not already in PATH), rather than the insecure Windows behavior, and this is indeed the current situation.  The current behavior is documented ("a full or relative path"), but a footnote that this differs from the msvcrt behavior would probably be a useful addition.  So I'm changing this to a doc bug.  (I have verified that ./ works, I have not verified the msvcrt behavior.)