I think JD Caputo hits the nail on the head when he says "we (FMA stylists) train to stay in the pocket." This means we train to fight at close or medium range, exchanging continuously so we learn how to flow, how to counter, how to spontaneously spot or–even better–"feel" the options available in any given situation.
I see this locked position directly in front of the opponent (in the pocket) in knife sparring, stick sparring, and in the knife-and-stick drill known as "lock and block." The fatal flaw of this style of training is YOU DON’T WANT TO STAY IN THE POCKET. GET THE $#@^ OUT!
I’m reminded of the Jiu-Jitsu instructor, Matt Byers, whose video I posted earlier. In jiu-jitsu you’re going to get on the ground to learn how to flow from move to move until you instinctively sense what your options are in any ground scenario, and can move automatically. The only problem is, you don’t want to be on the ground!
The whole purpose of mat training is to survive if it goes to the ground, but to get back on your feet as soon as possible. As Instructor Byers found out when he went to the ground in a bar fracas, although he immediately felt comfortable ("I know my way around this."), he soon found out that on-the-ground flow is part of the training, but tactically, the idea that "I’ll stay on the ground and out-wrestle him" is disastrous from a tactical perspective. When you’re outnumbered, and the beer bottles are flying, and people still standing can kick you in the head, mat wrestling can get you taken out–you’ve got to regain your feet.
Mr. Caputo suggests more elaborate sparring rules, but I think all that’s needed is to break up the flow drills, moving smoothly from technique to technique, interspersing them with hit-and-run (as he suggests) and flow-and-move-to-the-outside, meaning toward the opponent’s back. Guro Jerome Teague does a great job of breaking up close-range stick sparring and suddenly moving out to long range. I think this should always be the aim of these drills, to learn flow so that you aren’t overwhelmed by the opponent’s attack, but then to move immediately out to the outside and/or to long range.
DON’T STAY IN THE KILL ZONE! Sorry for the all caps, but I can’t stress this enough. Maestro Mulconery calls this the "cut zone." It is the area directly in front of the opponent where his blade can cut you up like a food processor. As important as it is to learn how to defend yourself in this worst-case scenario, it’s just as important to learn how to break off and get out.