Well, like you just said, I don't think three quarters of the men in this country could FIND their own penises in their 600 pound flab rolls.
With both hands.
And a bloodhound.
BTW the results of that study only found that the average size is one tenth of a centimeter smaller for americans than japanese. Though I have to wonder what the hell a Japanese guy with a huge wang would look like.....I've seen my fair share of porn, never saw a Japanese guy with more than like a 5 incher. In American porn the guy could have a 10 incher, easy...
Not to mention that with obesity can come diabetes, and that can cause erectile dysfunction. Maybe that influenced the american numbers.