I record using multichannel microphone arrays because that's the best way I've found of fueling the teleportation time machine.
The techniques, well applied, provide additional degrees of freedom that are simply unavailable using only two microphones, and directly address some of the difficult constraints under which tapers operate in contrast to how professional recordists operate.
It can be done in a lightweight, easily managed, relatively simple way. I usually setup and break down faster than most 2-channel tapers. But even if not streamlined that way, the choice between "light/easy-setup" and "the best recording I can achieve" should be a personal one each taper needs to determine on their own terms, is it not? Its is not a binary choice but more of a sliding scale, each taper finding their own comfort/satisfaction zone.
Yes to M/S.. as the center of a microphone array. Simplest arrangement is M/S between a pair of spaced omnis - a four microphone arrangement that works really well, better than either pair on its own in most taper situations IME, and is a relatively simple one that is hard to screw up. This is the "more than 2 microphone" configuration I recommend to other tapers interested in using arrays of more than two microphones. Yet even with this simple 4-microphone arrangement there are strategies for optimizing the spacing between the wide pair, and how far forward of that the M/S pair is. In more difficult acoustics, swap the omnis for a more directional pattern, pointed at the PA. The biggest practical challenge is how to effectively space the wide pair.
Don't like it? That's cool. Other folks do, that's cool too. Its good that we don't all like the same things, or do things in the same way.
Run a multichannel direct feed sometime. The results are extremely better than running a ton of mics, or even stage+board.
Not if you do it right. Sure, have done that. Not what I'm looking for most of the time.
Aren't you concerned with phase cancellation? Isn't almost impossible to avoid with running multiple sets?
Its impossible to avoid using just two microphones, unless using a coincident pair configuration. To be absolutely safe on this account, record in mono.
I have seen some really questionable techniques by some tapers mixing 6 or more pairs..why?
I see plenty of questionable two channel techniques as well. This gets to the deeper issue I think, which is optimizing any microphone arrangement to work well in the particular situation. That's vitally important for two channel configurations as well as more complex ones. Yes, with additional channels the complexity multiplies rapidly and unless strategically addressed can get out of hand, but the fundamental issue of optimizing the arrangement applies to any number of microphones.