Think about Jay compared to Ronnie Coleman. Jay reportedly eats 10 times a day, many times the calories of Coleman. More calories seemingly than any other bodybuilder. Ronnie eats reportedly 4-6 times a day only, the same things every day. Not too many calories. I would certainly conclude that Jay has pretty bad genetics in that he does not process food efficiently. His whole day is spent consuming food.
"in that he does not process food efficiently", [whatever that means] maybe. But think about this. To be as good as Jay is, Jay eats 10 times a day. You've got to have some discipline to eat this consistently/frequently/etc. Jay must have some damn good genetics, as far as being able to work very, very hard goes. And his genetics for being able to mentally handle dieting (whether that means eating 10 meals per day in the off-season, or dieting for a contest) are probably great.
Some people get it done because they have great genetics for physical aspects, but cant work hard; others get it done because they have great genetics to dig deep (mentally), but may not have great genetics regarding physical aspects.
Regardless, I'm sure Jay has his strengths and weaknesses, genetically, but overall, I wouldn't go as far as saying he has poor genetics.
Just an idea to consider.