Tyson Gay (5'10.5ish" or 180cm) has short legs but made the most of them maximizing his stride length. He has very small feet allowing for maximum turnover.
Bracy may be shorter at 5'9" but he looks good sized and not too stubby.
Remember, Nesta Carter, Michael Frater, and Mike Rodgers are all 5'8" and they have run 9.85's. They are stubby short guys, and ran 9.85's consistently.
Bracy when he gets a little older should be in the 9.80 range consistently if he gets better transitions and endurance. He could be even faster.