The so called "fragility" of Sigs (speaking of the full size 5") were due to SIGs initial reasoning that quality outsourced parts from many quality vendors could just be assembled with little to no fitting and sent out into the publics arms
i think an early mistake was to base their decisions on an expert who didn't have alot of experience in production line manufacturing
S&W utilize the Schwartz safety system and have had numerous problems with their external extractor
are you saying that these 2 things are related or just taking a shot at the Schwartz safety system? their FP safety is my one major objection to the S&W 1911...but i believe they have corrected their tolerence problem with them, much as Sig has addressed theirs'