You are definitely right on the eclecticism part. I'm probably too
eclectic myself, so 8 hours straight of programming is horrifyingly alien to me. My particular activities differ from yours of course (they're much more silicon oriented, for one thing), but I do find myself wandering off mentally if not physically after just a few hours.
There is however a very fine line between good eclecticism and bad time managment :). I probably suffer more from the latter than I benefit from the former.