It just occurred to me that the reason why one of the judges found my old ale overcarbonated may not have had anything to do with my processes or a mistake I made. Instead, I think it was because I used rye as part of the malt bill. Unless I'm mistaken, rye and wheat end up supporting great, foamy heads because of the particular proteins that are involved. (Sorry, I can't get more specific... In fact, I'm probably misremembering even that).
I may not have screwed up! It's possible I just confused the judges with an unexpected grain.