I won't claim to know the answer to that one definitively, but actually if that is true, I wonder then what the difference is between an MQA decoded MP3 track and an MQA decoded FLAC track? Is the MQA decoded output exactly the same or does the fact that the "base encoding" is MP3 vs FLAC matter? Obviously that file when decoded by a non-MQA capable decoder would seemingly be different just as "standard" non-MQA tracks of those same file types are right now (regular MP3 vs regular FLAC). I don't know the answer there but it is an interesting question.

And yes, from a comparative standpoint, playing back that same file in non-MQA mode vs. MQA could demonstrate dramatic difference. The benefit here would simply be less work. Keeping a library with a single version of all tracks where the quality of output then depends on MQA compatibility or not. It's an interesting concept.

Various