[huggah]

How on earth can we usefully generalize from the experiences of white men born ~1918 who attended Harvard? I think longitudinal studies are massively important, and I'm all in favor of them, things like:

"Alcoholism was the main cause of divorce between the Grant Study men and their wives"

Don't really give us that much of a clue about how alcoholism (for instance) affects everyone else. I suspect it's similar; but this doesn't give us any data on anyone who isn't in a very very specific group.