So I know this question seems kind of confusing at first, so allow me explain it the best I can
There's a lot of questions that are centered around things like "What should my sixth team member for my LeafGreen Playthrough be?" or "Should I use Raichu or Luxray in Platinum?" which are all in the right place, but there's some for games like Mystery Dungeon Red & Blue, for example, that end up on the unanswered list for such a long time, that the people asking them either resolved the question, beat the game, or have become inactive on this site.
So, what I'm suggesting is for Old Playthrough Questions to be closed, as long as we know if the playthrough is complete, or if it's resolved
Of course, we'd have no idea if someone has completed a Playthrough or resolved the question unless they post about it on their wall or something, which mods shouldn't be checking and moderating 24/7, so maybe people could edit or comment on their question that they've completed the playthrough or resolved the problem, and if they resolved it, explaining how for other people to know (if it's re-usable, if otherwise, then there's not much of a point).