Horses who've won both the Derby and Preakness since Affirmed in '78 are...what, like 0-for-11 in the Belmont now? That includes horses who looked far more impressive and dominant than I'll Have Another did. No matter how good a horse looks beforehand, that 1.5-mile track can make a lot of them look mediocre.
You have to bet against him. It would be great to see--I haven't seen a Triple Crown in my lifetime--but there have been too many sure things--Smarty Jones, War Emblem, Big Brown, etc. etc. etc.--who fell short.