Any pics of the delaminated pulley? I guess as the cars are around 20 years old now this sort of thing might occur more frequently. Regarding solid pulley designs I'd stick with the OEM pulley as harmonics can be pretty unpredictable.
Back in 2011 Aston Martin's ill-fated AMR One LMP1 prototype Le Mans car didn't even last 24 minutes never heed 24 hours when the harmonics destroyed first the aluminium alternator drive pulley then, when they replaced this with a steel one the harmonics broke the crank pulley. By Aston's own admission they were doing the engine development on track, not on the dyno like the better funded teams such as Audi, Porsche etc.