After UCLA's Patrick Cowan in the preseason, I can't think of any college quarterback who injured an ACL or had any significant consequences of getting "rolled up on" at the end of a throw last year. But Tom Brady goes down:

And all of a sudden nobody feels safe:

Mindful of the injury that sidelined NFL quarterback Tom Brady of New England last season, Oklahoma State quarterback Zac Robinson is experimenting with a protective brace on his left knee.

"It's a precautionary deal," he explained. "So many (quarterbacks) have gotten rolled up on. I feel good with it. I've worn it the whole spring so far. After the first five minutes, I couldn't even feel that it was there. Me and (head athletic trainer) Rob Hunt talked about it, and I thought it was a good idea."

To recap: Robinson is not injured in any way. But, as John Taylor points out in College Football News, the brace is so unobtrusive it apparently took more than three weeks for a reporter to ask about it. So why not wear it all the time? If I was Robinson, I'd be more worried about my eyes, anyway.