Originally Posted by Gary1911A1
I agree and will add is there really any good reason besides a class three malfunction where a fired case doesn't extract where one would want to do this.
It is rather important that a type three malfunction can be cleared without breaking the pistol.
Apart from that the only other significant reason I can think of is as a means to top up the pistol with a round in the chamber before inserting a full magazine in a way that eliminates the possibility of bullet setback and a lot of administrative fiddling with magazines and part used rounds. In that case I would let the slide forward gently and push it to so that the extractor engages. I would then partly withdraw the slide to make sure that engagement had taken place before inserting the full magazine.
In the really rare situation that you have used up all your loaded magazines and have run dry but have loose rounds it is far quicker for one desperate shot to tip the pistol to the left, drop in a loose round, tilt it downward, drop the slide (you do need to use the slide release lever but might need to rack as well depending on the pistol), aim and fire. In this I speak from the experience of having practiced it. The alternative of removing the magazine, holstering the pistol or holding it in your teeth, putting rounds in the magazine then reloading as normal does not work well against the clock even when you have a bench to save your teeth.