SubThermal:
Having practiced together with NIS(Nationella InsatsStyrkan), the Swedish version of the FBI HRT, I can agree with you in that what you say about multiple snipers is the optimal solution in theory. As all soldiers know, theory and practice do not always meet.....
As for having multiple headshots, that is not always the best solution, just like police all over the world(primarily in the US and UK) have started to find out that firing rounds through the heart isn't always such a good solution, after it has led to the death of quite a few police officers.
A shot through the shoulder or thigh can also incapacitate, as evidenced by the hostage situation in Örebro, Sweden in 1986. 3 men under the influence of PCP and armed with AK4 battle rifles took an elderly couple as hostages. After a stand-off, the police were given permission to act, and the first shot was fired through the thigh of one of the suspects, whereby his muscles were torn, and couldn't hold his weight, so he toppled, and lost his weapon, and the two others were apprehended after they had been tear-gassed and flashed, one of them shot through the shoulder, his arm becoming useless, whereby his weapon was dropped too.
The police sniper was armed with a sniper-modified AK4(Now they have AI AW rifles).