Back in 1990 when the project was in production, the choice was made by the company to use the mixes that Ron Jones was given after the sessions on his DATS as the source of their master.
Thanks for the info, that is interesting to know. I guess there's a silver lining in that if the old release had perfect sound, there would have been less demand for the expanded edition.
I have only rudimentary knowledge of this, but my assumption (possibly wrong) from what you've said would be that the session DAT was some sort of board mix or the listening mix while they were recording it? I'm further guessing that the show was actually mixed with the multitracks, so that's why a proper two-track mix was never created.