Personally I don't mind reposting. Say you posted then "ooohh I just had an idea how I could have done that better". But of course this also can lead to abuses like everything else, like seeing someone else's post after your post and making modifications based on imitation or inspiration from that post. Maybe contests posts shouldn't be made until the last week of the contest and preliminary posts should be labeled as WIP. Ok so I'm all over the place here. :)