My answer would be from a bullseye competition perspective. Most will agree the 9mm is more accurate than a 45acp in the 1911, however, in order to achieve the most accurate loads in the 9mm, you have to run them hot. That cancels out the less recoil argument since a 45 acp can be loaded down considerably and still achieve excellent accuracy. Another aspect is that running a 9mm hot can crack the frames. The military pistol teams experience this from time to time. Its no big deal for them since they travel with their own gunsmiths and their portable shops. However, it would be a big deal to me. I have 45's that probably had 100,000 rounds thru them and they are still going strong with some minor tightening up from time to time.
Phil
