is this running only? I'd say your general take on my history is accurate. Also, I've noticed that my max hr seems to have decreased by 5-10 bpm over the last 10 years, with some proportional change in zones. I haven't adjusted my zones in a while, but probably need to.
You get two guesses what's going on in those shortish super-slow sessions. though we have been speeding up a little recently.
one guess per increasingly-ambulatory bundle of joy?
what's up with the ~5:20, ~10k at 110(!) bpm? meditation on the go?
Running with the munchkins while they cycle?