Hey all, I can agree with Greg in that I have never broken a Campy crank and I think as Mike K. correctly said, all vintage cranks have the possibility of failure. Personally, I think an additional "missing point" is that other Italian manufacturers, i.e., Gipiemme, were well ahead of the curve as compared to Campy in this regard. I have owned and used a 1980 vintage GPM crank that had extra "beefiness" (for lack of a better word) at the crank arm/spider arm junction. Many of you already know that Campy didn't start making any design changes to their SR/NR cranks until appearance of the "non-fluted"/"laser-etched logo" cranks; a good 5 years After GPM introduced their answer to this problem. Just something to think about when valuing vintage components. Here is one of these GPM cranks I refer to on ebay. I would only add that I do not know the vintage of this crankset and it appears that the seller does not either.
cheers-
Dave Anderson
Cut Bank MT