It's not as uncommon as one might think, actually. Though certainly some horses, once having unseated their jock, will either make a beeline for the backside or run willy nilly before apprehension by the outrider, those that stay "in the game" are at a distinct weight advantage.
Anyone watch the head-on of the break? The 7 leaped like a stag out of the gate--I don't know how anyone would have been able to stick with it. Almost looked like the horse was about to go up in the gate and then the door opened and he went forward while still going up. Considering the height he got, it's probably fortunate that Cuthbertson came off instead of getting squashed or flipped on.
Life would be infinitely better if pinatas suddenly appeared throughout the day.
That had to be hairy for the other riders with the loose horse threading his way through the field like that, but man he did an awesome job all on his own, didn't he? How he waited and then dug in when it was time, and timed it so he hit the wire ahead a jump out. You gotta love those guys who run like that.
Wouldn't it be col if they ever had a riderless race? Never happen, but boy it would be interesting.