Another good suggestion.  This one would have to wait for 2.2.x as it would involve some changes to the DB (adding a field to track the last initiate request).

One thing here, it would actually be a field, and depending on the theme, it would show or not.

A definable lockout on an actually declined initiate would be good as well.  This way if they say no, you can't initiate for a specified time, or when they leave and come back as a new visit.