As someone who gets asked many more questions than he asks himself, I think this is a fantastic rule of thumb. It's annoying when somebody asks me a question which I can tell they spent no time troubleshooting. But, it's possibly even more annoying when I go check in with somebody and find out they have been spinning their wheels for a day and a half on a 5-minute problem without telling anybody. I would rather they err on the side of bothering me than burn hours upon hours of time.