SteveD's preview suggestion wouldn't work either - this site obviously has a gremlin in it who mischievously inserts spooling mistaeks into words after they have been posted - it would just wait until after the preview screen if there were one.
It should be possible to edit, however either time limited or until an answer has been posted. It wouldn't do if we could change questions after answers have been submitted - or would it...? Also a preview pane would be good. The tiny entry pane is too small to allow a decent assessment of what you have written. You can only see about 6 characters at a time.