The alleged theory is, once you engage hostiles and then, somehow, sense a lull in the action, you want to bring your gun up to full capacity, should their buddies show up or maybe they're just playin' possum.....

So you retain the partial magazine, JUST IN CASE you need those 2-3 or 1 round later.

As I cited above: Military encounters aside, there's NEVER been a case of someone getting into a firefight, then somehow sensing a lull in the action, performing a 'tactical' reload, getting into ANOTHER firefight on the way home, running out of fresh ammo, remembering you might have one or two in your pocket (which one was it again?) being able to retrieve that mag amidst all the coins and keys then blow out all pocket lint from the mag, reload your gun, all while taking incoming fire, racking the slide and have THOSE 1-2 rds save the day.

To me, not only is that a virtual impossibility, it's misplaced priorities. My FIRST priority is getting my gun fully loaded while watching for other badguys, not being distracted keeping track of a partial mag (or is it empty?).

John Farnam, a famous gunfight instructor, teaches to drop the mag, insert the new one and then CYCLE the slide. His reason is to make sure you have one in the chamber. How do you know if the slide didn't catch the slide stop and slammed home empty? There are two sides to that argument, also, but it's light years ahead of retaining a partial (empty?) mag for possible later use.

A "tacload" is useful three times:

1) when utilized as an adminstrative type loading.
2) when you're involved in a shooting in knee deep water (ala Katrina.)
3) you don't want to leave incriminating evidence behind.

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