It's not fairly recent, just an ongoing struggle. He does it when he rolls because he just smacks his feet together and makes no attempt to be gentle about it. He has shoes on because he has a congenital defect in his coffin bone where he is missing a chunk and had a break on one of the weakened points so the decision between vet, surgeons, myself and farrier was to prevent future possible problems by stabilizing the foot with a shoe. He's very sound and doesn't knock himself when being ridden or out running around.
If he didn't roll I wouldn't have a problem...but he loves to roll ;)