Yeah, I can see how too much passion can burn you out. I'm borderline obsessive about some of the things I do in my spare time. The thing is that I really like doing them but taking a break from too much intellectual stimulation is probably a good thing. I'm probably not old enough to know but it may be more necessary for older workers. Probably also the reason I can handle it relatively well is because I don't have a wife and/or kids. Again, all the more reason to take advantage of passion when you find it in the younger folks!