Bruce, I process Tmax 100 which has an expiry date of 1991, so it is obviously a different version.
I use D76 1+1 (home-brew).
I always process 4 sheets at a time in the smallest tank on a 2509 reel, using 300ml of solution.
I just checked my last developing run sheet and noted that I developed for 10 min 15 seconds @ 20.4 C
The negs were quite well developed and they have a full range of tones. I had one of these negs on the light box in the darkroom because I printed it last night, it printed well.
I check my dev temperature with an industrial electronic thermometer which has been calibrated and is re-calibrated every 6 months, that is why the quite precise measurement.
I use a CPE2 Jobo with lift and use the high speed for the first 15 seconds then I switch to the slow speed setting for the remainder of the process.
If I'm using this film in low contrast lighting I will add 1/8 stop of developing time to give it a bit of a bump.
I print with a diffused enlarger and find these negs print around grade 2 3/4 to 3 1/2 on my enlarger, leaving me room to go either way for a different contrast, if required.
I don't use a pre-wash!
Mick.