Mid-side decoding issue - Total silence from the two side tracks

[bouldersoundguy]

One of the advantages of M/S is good mono compatibility.

The other advantage is that you can adjust the "spaciousness" of the stereo image by adjusting the relationship between the M and S channels. That was evident in the difference between Porterhouse's first mix and my first mix. As you blend then two, the strength of the side channels changes. You can't do that with an X/Y or other 2 mic techniques.

You can directly convert X/Y recordings to M/S signal format and do the same width adjustments. Actually you can do it on any stereo signal, but there's no guarantee that it will collapse to mono gracefully.