This is my first entry. I've occasionally viewed entries over the years but was finally moved to register after my second Shimano pedal arm breakage/accident yesterday. The first was a few years ago. I was riding in Albuquerque ascending a small rise to get on a trail. Out of the saddle and WHAM!!!! Drive side down , smashing my head against a steel guard rail. Helmet caught the brunt of the impact. Knocked unconscious for a few seconds. A passing cyclist helped me up and we realized the crank arm was cracked right in the middle. VERY SCARY. Yesterday, climbing up a moderate 4 to 5 % hill. Out of the saddle. WHAM!!! Drive side gives way. Down like getting smacked by a 1000 pound gorilla. My riding partner , who was 2 to 3 feet back came down on top of me. Dura Ace 7900 with Keo Blade pedals. Cracked right at the very end, i.e., at the pedal. Every mechanic that I've mentioned this to says they've never heard of such a thing. I'm 190 lbs and ride a lot. Maybe 8000 miles a year. The roads in New Mexico are medium rough. You expect a certain amount of "wear and tear"...but what the....???????