Someone has suggested I delete/close Is there a way to disable or limit system xrandr probes? because I am no longer experiencing the bug that prompted me to ask it.
Personally, I think it's still an interesting question that an experienced X.Orger could answer (even if to say, "sorry, it's not possible"), and might be useful to others with the same or similar problems. (I guess this is the opposite of http://meta.askubuntu.com/questions/1898/how-should-i-deal-with-old-unanswered-questions-that-are-unlikely-to-be-answered where the OP wants to get rid of a question that doesn't directly affect them any more.)
Are these reasons inappropriate? Why should I close this question?
(Bonus: Should I reword it to minimise/remove references my original issue? In this particular case should I ask to migrate it to Unix/Linux SE?)