That has not been my experience with any aluminum frame or part failure. I've broken two aluminum frames and many aluminum wheels. None of them "fractured catastrophically". If you think about the material it's fairly easy to see that aluminum is unlikely to fail by "shattering" as well. Aluminum is soft and not brittle at all. It generally tears rather than experiences fracture. Aluminum also makes a lot of creaking noise after it cracks just like rseeker's bike did. I've often found that my bike "creaking" is due to some broken part that I just failed to understand was broken.

I've also broken 2 steel frames...one several times... and several steel parts. Steel, on the other hand, has always fractured catastrophically like aluminum is supposed to do. The steel frames were just fine without any noises and then they went "ping!" and were broken. Same with steel spokes and pedal axles and hub axles. No warning, no bending, no creaking. They just broke.