I’m not sure I am totally onboard with this, or all the talk about data scientists, TR are not trying to fix string theory, in fact they created the answer, they created progression levels, so the answer can be what ever they want it to be, as it doesn’t have to fit in with anybody else’s “model”, they are having problems with the question, and have full control on both the question, and answer
So I would suggest that a lot of their problem lies with the fact that they don’t record workouts very well, an in a way that isn’t compatible with if the same workout was recorded on a external device, if you do a 6 x 3min V02 workout with 3 minute gaps in TR , and take a break in the middle of the V02 sessions, and then extend the rest periods, this does not affect your PL as you are given the score the workout intended, rather than what it achieved, but if you recorded the same workout on a Garmin would have 12 x 1.5 mins with 4 min breaks (for example) which would give you a different (and a data scientist would probably agree,) a more correct PL
Even if TR wanted to re populate previous PL’s they can’t do that as they don’t (seem to) record that information, which I’ve always found a little strange
My concern for TR is that it is neatly 2.5 years since Nate said they had a working version of outdoor workouts, and if it has taken this long to get it to beta, have TR built it on rocky foundations, although PL’s are great(ish) they aren’t really AI, and in that 2.5 years a lot have moved on, we have several apps from small companies doing actual AI training, Join, Breakaway e.t.c. TrainerDay are looking to beta test a ChatGPT based workout recommender, and are building a adaptive version of their (superior, if you buy into their training philosophy) plan builder, and Xert are promising “something market changing” (posted in this forum
And none of these companies seem to be looking at PL’s and thinking, hum … we gotta get us some of that action
*** Edit
All of the above is just speculation