I've had 0 flats in 4 MS150s, the training rides leading to them, and the 900 miles since I started riding again recently. Also riding in Houston, but only the latest 1k miles have been rock and glass strewn city streets. I'd say I've been lucky. In fact, the only reason I'm changing tires is cause I had to lock the rear wheel for a second, and now have skidded to the threads. Old tires were continentals.... guess I should check what tire exactly and give them an awesome review.
BTW, I do bunny-hop cracks, debri if needed, so thats one thing i have over some other riders.
Sidenote, did you get the flat at the Katy flatland? One of the guys in my group got one towards the end. Pumped it up, and rode hard till it went flat within the Katy Mills parking lot... then sagged
His was a shard of glass.