well that makes sense hehehe
yup, when i was first learning under my mentor and for the years that followed up to me switching to GH flora and the lucas method (modified), it was peters 20 20 20 veg and 2 weeks into flower and then peters 10-52-10 for flower. There was another granulated product that was added in flower but I’m not sure where we got it from as it was always in a big ziploc. Looking back I am guessing it was mg/ca and K. Back then I was just a garden apprentice and just worked off the feed charts I was given. It wasn;t until later and when I was on my own that I started to do my own learning and getting deeper into nutrition.
as per root pruning. One of the growers I know …20 years ago now,. He grew a constant flow system in long 12" diameter tubes with cutouts for large net pots. I am not sure exacly when in his cycle he performed his root pruning but he would lift his pots and prune his roots right back as part of his method. He was growing double dutch and I do have to say, his finished rooms and cured flower always impressed me.