Seen it once on an OCLV frame...this guy must have been completely oblivious because when I got my hands on it it was almost all the way through the chainstay.

No personal failures for me, but about half a dozen carbon (OCLV actually) and one Ti failure-that was a funky sort of shearing within the downtube just aft of the headtube. I wish I'd taken a picture of it because it was quite interesting and I can't begin to describe it.