Very good proposal, ++.

This would also be a place to use Javascript for a good purpose, for once (since it is what JS was really invented for initially): the submit button has onClick bring up a confirmation popup that sets sure=Yes before submitting. If the user has disabled Javascript, the sure parameter will be missing, so the engine returns a form with a <input name="sure" type="submit" value="Yes">. More convenience, less server load.

Makeshifts last the longest.