OK, so from all I've heard, even though TMT "performance testing" activities date back to the mid 1980's, it was around 1991 or so that TRA first actively proposed to use an "approved motor list" and limit launch activities to motors from that list (though this wasn't in effective force until some years later).
Now as far as I can tell, as of 1991 this was before all the weirdness, the long-term personality conflicts, the regulatory FUD, all of the "history" (whose sizzling shrapnel we still encounter years later). TRA hadn't even (AFAICT) started treating Jerry like some sort of outcast yet - he was one of the first suppliers to have his motors listed IIRC; the "great falling-out" seems to have come along a bit later.
Even NFPA-1127 - with its attempt to put a face of "proper consumer rocketry"-type legitimacy on a facet of the hobby that had been started as an explicit escape from the limits of "proper consumer rocketry" - was yet to come, as was TRA's attempt to adopt a public image of "just like NAR except with bigger rockets".
So why was such a list being proposed as of 1991? Presumably the existence of an "approved motor list" would imply the existence of other motors, not-approved: otherwise it simply becomes an exercise in listing every known motor type. (At which point, why bother - just say "run what you brung" and publish motor lists/tests/reviews, perhaps, as an information service - give Bruce lots of pretty graphs with which to fill up the pages of HPR magazine, if nothing else...)
So what motors, back then, was TRA expecting to want to keep _out_?
-dave w