Paul McGowan: "What is PRaT and do the British do it Better?"
https://www.youtube.com/watch?v=7YGgMpX3XII
FWIW, he says, regarding pace, rhythm and timing, "I think it’s one of those things that, if you haven’t ever experienced them, it’s hard to describe". He asserts that, although PRaT is not a top priority for him, he's found it can and does vary, depending upon the gear used.
This is my experience as well, although I’m in no way suggesting I’m in a remotely similar category when it comes to experience/knowledge as P. M.
To me, it’s best described as a "propulsive quality" that cannot be defined solely in terms of BPM. Scientifically, this sounds ridiculous but for some of us, at least, it’s palpable. Perhaps there’s an as-yet-unexplored physiological aspect to this that comes into play.