uncleyug, as I suspected, this is an ordinary coincident stereo microphone with left and right outputs. Internally it uses M/S to generate those left and right outputs, and that's certainly an interesting bit of applied technology, but it means that in the end, you simply have a coincident pair of directional microphones there.
Compare this with microphones that generate an M and an S signal directly (the S mike always has a figure-8 pattern), which you can then dematrix into left and right (choosing your own proportions of those two signals, as well as the pattern of the M microphone), or you can record M and S and then dematrix later on, at home while listening over your favorite loudspeakers so that you can choose the proportions to match. That's M/S recording.
You probably know this already, but any coincident pair of microphones can be matrixed into M/S and vice versa. But the whole thing about mids and sides, you can forget as far as your original question is concerned; you have two coincident stereo microphones of the same make and model, is all.
OK. If you have a pair of coincident stereo microphones aimed a few inches apart, with some angle between them, more or less as if they were ordinary, single cardioid microphones in an ORTF or similar array, and if the outputs of those microphones are paralleled, what you have is rather difficult to characterize because it is very irregular geometrically, but it is symmetrical on a left/right basis, so in that sense it's not unsuitable for stereo playback. Still, whenever you mix together the signals from two microphones that are only a few inches apart, what you'll get is reinforcement of low frequencies and then, starting at some upper midrange frequency (that's a function of the exact distance between the microphones) you'll get alternate bands of cancellation and reinforcement--what's known as a "comb filter" effect.
However, your two microphones per channel aren't aimed in the same direction, so their cardioid pattern would tend, I think, to reduce the comb filtering effect somewhat.
All in all, I really wouldn't recommend doing what you did, for all the reasons I mentioned earlier (loss of sensitivity and headroom) and because the resulting pickup pattern from the two mikes combined per channel would be irregular especially at high frequencies.
--best regards