Good point Steve! At the end of the day too, it's important to realise that even transmissions sometimes don't "care" what we use. When I was having trouble with the clutch and transmission in my firebird, I called the dealers to ask what the approved "lubricant" was for the transmission. One said gear oil, one said ATF, one said "Whatever you want, engine oil even...". I opted for the ATF, in the hopes that in the dead of winter here (-40F ish bad days) the car would not try to drive itself even in neutral anymore. The ATF was also reported to be easier on the syncros in the transmission, and I was all for that.
Soooooo, even though the original spec was for gear oil, the ATF was an upgrade that improved usability.
HA! That even worked out as an analogy!