So, does this mean more than two microphone positions, or should we say, speaker positions? The biggest limitation of MIR to my ears is the lack of stereo field from the ambient microphones and the inability to have a more realistic approach to capturing what an orchestra sounds like both in the room while still capturing a more intimate sound from an instrument.
For this reason, I typically have to use two to three recordings and merge the audio, and mix carefully (two microphones, one at the conductor location and one near the front of the room, the so-called 7th row microphone, another recording with two microphones at the left and right of the room about 1/3 of the way back starting from the front row of the audience, and a final stereo set of mics at the far back of the room on the back left and right walls).
I then mix this in 7.1, using the conductor location as the center, the 7th row also mixed in as center, and I eq the 7th row microphone to under 120 Hz as the sub, and the additional sets as the mid rears and rears. Maybe it's overkill, but the reason we are working with samples and impulse data is for ultra realism, ultra near perfection that is not possible in a live, one take recording.