If that had been mine I would probably cut the little projection off and continue running it. The reinforcing fiber is a continuous spiral and I'm sure the belts are well over sized so the there wouldn't have been much reduction in total strength. Kind of like the belt type tracks on tractors. A rebuilder of them told us in a Lion's lunch presentation that they will retread a belt with breaks at the edge, but not in the middle. They'll retread a track with up to about a 20% reduction in width from breaks. I know a tractor track ain't the same as a Spyder drive belt, but the principle is the same.