There are very few silly questions, even if you feel shame faced afterwards. Keeping "brain fart" questions around can help newbies and others who have a momentary lapse of memory get back on track quickly and help show that we are all fallible. I'm sure I've posted some fairly sub-par questions, 02.5 == 25 - WTF? comes close. There are many silly nodes I could have posted that were caught while I was typing up the node.

In any case, keeping your node around to help others who hit the same issue is a large part of what this site is about.