Although this is possible, I have been doing all of my own work on numerous bikes with aluminum cotterless cranks since 1971, and this is the first time I have ever cracked a crank at the spindle eye. (In a completely unrelated incident, I once broke a 1970 Sugino crank across the pedal eye during an out-of-saddle climb -- ouch. )

That's about the only rational explanation left. When I mounted the cranks onto a Campagnolo cartridge BB, they did not seat quite as deeply as I would normally expect from past experience with various brands of cotterless cranks, including TA, Stronglight, Nervar, Ofmega, and Sugino. It was the same effect as trying to put a European crank onto a Shimano spindle, but less pronounced. Did Campagnolo ever vary the cutoff size of its 4-sided 2-degree spindle tapers?

---- Dr. John