Any experience good or bad with clutch fans on your mopar?

Not a Mopar but I built a 70 Monte Carlo with a 454 and Hydro roller cam about 10 yrs ago. ( traded a dirtbike for it) and while I was setting the timing I blipped the throttle and the water pump shaft sheared off!
That was exciting! Lucky to be hear today....
I think the fan was out of balance and/or cheap waterpump