If M1 and MW are weighted toward the lower frequencies, then I would think that the ID's would be at least "kind of" close. But, they're not even kind of close. They're massively different in TNSS's unmasking test. I can't imagine how a slight weight difference in the frequencies, would cause such a massively different target ID. That's why I'm thinking MW is using either 5 khz or 10 khz, OR, there is some other very significant difference in Beach mode that causes such drastic ID difference. Note how I asked TNSS to try the single frequencies in that test, and he confirmed that the single low frequencies were behaving like MW.
Also, on 2 different sites, BW would ground balance to zero. If I remember correctly, that is a failed ground balance. Further to that, on one of the sites Park and Field were fine for noise and stability, but Beach mode was extremely noisy and unstable for some reason. I guess it was some odd emi on that site that was severely affecting Beach mode, and not Park or Field.