I guess the one that really confuses me is running the slide after a tactical reload. If you run the gun dry, power stroke or slide release make sense. If you have to clear a malfunction that requires the magazine to be stripped of course the the slide will be manipulated to chamber a round after inserting a fresh magazine. However, lets say you engage a target and fire the number of rounds it takes to do the job. Then you scan and asses the area. After it checks out you decide to top of the gun, so you bring a fresh mag to the gun, swap mags, retain the old one. Some instructors/schools would have you cycle the slide at that point, and that is what I am confused about. Same guys operate the rifles in the same way.
The only thing that I can think of, is that the above mentioned method would work with pistols that do not have designs that hold the action open after the last round is fired, and would eliminate the possibility that you could perform a reload and leave the chamber empty (makes sense in the AK manual of arms in rifles). Someone please enlighten me.