Ian,
My high school history teacher used to say that if we only read History from newspapers and magazines, we are doomed to repeat it.
D-76 worked consistently fine with TMY from Day 1. At least it did for me, and several other folks I knew. I had the good fortune, however, to be given a quantity of TMY in unmarked yellow boxes. My contact at Kodak said it was like Plus X and it is EI 400. So, I shot a roll in the studio at 400, and did a couple clip tests to find a development time, and that was done. When TMAX developer appeared later, it worked very well, giving a little longer straight line than D-76, but was very similar - just a liquid !
What TMAX was, was a pleasant alternative to HC-110. VERY different beasts are TMAX and HC-110.
I did not have the disadvantage of reading 'experts' months later whose work was simply shoddy, who claimed the strange results you referred to. At least American 'experts' were wrong, except for Sexton. This was a matter of interest to me at the time; I printed for a couple shooters whose work was developed by highly reputed labs who catered to pros, and I SAW the problems folks had with D-76 and TMY. Rather, I had to print the stuff, and very quickly I began to hang out at the labs to find out just what they were doing.
What I saw at a couple operations was a casual and incompetent atmosphere: TMY was treated as it were TX, with the attitude of "Anything goes, it'll work". Temperatures were inconsistent, times and agitation was variable, and often the personnel was poorly trained and supervised.
I can't account for what other people did, but there were lots of folks who were attentive and correct, and got great results.
I'm not offering this as a comprehensive history, simply an anecdote from a primary source.