LOL LIke that, or my personal fave is that Harry didn't get his broom in the proper place in the book. And people get really uptight if you say that if the author doesn't mind, we can't really complain... heh.

I can't see anything right now, but I dunno if JKR would introduce something for no reason. The only thing I can see that wouldn't be necessary to use in OotP is if Grawp helps in the impending war. They could get away with that.