I don’t recall if it’s Palmer or Spencerian - but the “write with the arm, not the wrist” was key to my (re)learning cursive. A few colleagues and I, who stumbled into a very strict no-electronics but very information dense corner of the workplace, got into fountain pens. We agreed that if we’re going to use “fancy” pens, we’re going to write “fancy”. At ten or more pages each of varyingly legible script/person/day we happily tormented those who’s jobs were in fact to review the notes for removal from the building. I was one of those too, but I at least could decipher most of our product!
Now that I think of it, all of us were at the time 45yo or older. The “darn kids” had a really hard time with our “hieroglyphics” if we weren’t there to translate. Archivists will have a field day sometime in the distant future…