It is easy to armchair general this one, but I think you will find that in mass surrenders (this was one) prisoners are typically not immediately strip-searched. You march them into a compound, and then search and interrogate them.
While that sounds nuts, it is less nuts that playing a game of "Red Rover" with 2000 armed troops attempting to surrender, and having them come over one-by-one at two to five minute intervals to allow an individual search of each prisoner. Some brave boy is going to figure that you are afraid of them, take his AK and "unsurrender." Then some more are going to change their minds, and all of a sudden you have opposition again.
You are better off putting them in a cage, and then searching them for weapons. Of course, if you do violently resist after capture under international law you are a criminal, and can be charged with murder or assault. That is why escaping P.O.W.s (in real life, not the movies) rarely kill guards or pursuing soldiers. They then are no longer P.O.W.s, but rather criminals.
Of course, when you are dealing with wackos like Al Qaeda, all bets are off, but it is a bit unfair to the N.A. troops to dis them for assuming that the rules of war would be followed by their opponents. After all, this is Afghanistan, where warfare is merely another contact sport like hockey or football. It's like getting down on a football player for not expecting to get clotheslined.