While it may indeed be true that fat chicks are academically "cleverer" than fit ones, the reason is far less scientific:
Thin chick > read lots of books and eats chocolate while doing so > clever fat chick.
Fat chick > can't get laid 'cos fat > reads on own > clever fat chick.
Thin chick > has a life > not so clever thin chick.
QED
Oh and the offspring being cleverer... well surely a fat chick is more likely to have a fat sprog, who by virtue of being fat is destined to be "clever" as already established.
Bit of a no-brainer that!
So the benefits of having a fat wife: cleverer person, cleverer kids.
The drawbacks: huge shopping bill, crap sex, repulsive partner, embarassment when out together in public, kids will be teased for the first twenty years of their lives.
I wonder how fat the woman that co-ordinated this research was?