While recently dismantling my crapbon Pinarello F3-13 I found it cracked in the down tube near the BB and don't know how long I rode it like that. But at least it didn't "asplode" on me and surely I must have rode it some distance cracked.
It doesn't really bother me because a used 6 year old carbon frame is pretty much worthless anyway and all the value is in the groupset and wheels. I never really warmed to riding it and my steel Olympia kills it so not complaining just relived it didn't snap in two at 80kph.