IDPA Shooters drop slide on empty chamber??
I have been doing this in IPSC for the last 21 years and IDPA for the last 3 years. Guns, Para 16-40 (1911 wide body in .40S&W), Glock 21, Springfield Armory 1911 45ACP. No issues and all still shoot just fine. Lots of matches plus practice at my Home ranges doing the same. For me this is an "Old Wives Tale" along with shooting lead in Glock guns......YMMV.