Definitely. I think this function would go a long way to helping HubPages appear more professional and quality-filled.
For those of us who are working to improve our writing, answering, questioning, and listening skills it would definitely seems worthwhile to have the ability to correct our work.
How about giving Questions the same few minutes given to those who answer? Perhaps asking for indefinite time to correct Questions would be too much to ask for, but if answers can be edited by the author, seems that questions should be given time, too.