The myth is that they are shaved. A rattle in a bat and being tossed is nothing new, same with the wobble on a Stealth. It is known that when one of those 2 happen, the bat will most likely exceed the limits or be broken and then it's a safety issue. We took the wrapper off a Miken Chill, and a Worth 2Legit, and hit them in a cage. Both had a rattle after a bucket of front toss. If a newer bat gets tossed for a rattle, I'd be on the phone with the MFG getting a replacement without counting against the warranty!