no worries, I live under a rock and the science is always changing. Literally the first time I've heard this. Always room for improvement from bro science to actual science. over many years I may find something works for me, yet it could be for other reasons and not necessarily tut but rather just training until close to failure.
Recent data is looking pretty good in the sense that much of it is coming from trained populations and many of the study designs are structured sufficiently well to isolate particular mechanisms. Brad Schoenfeld seems to be leading much of this research.
The tl;dr for most of it is that more is better and that sufficient intensity is necessary for optimal gains. The only mitigating factor is that if one is doing 30 sets of legs in a week, they're going to be wrecked and likely unable to do anything else. The trick is to take one's total recovery capacity, which can be trained to a point and prioritize that among the exercises and muscle groups that yield the most stimulus for the desired muscle g
Full ROM works better than partials for certain muscle lengths and shortened ROM in the lengthened position may be superior for certain exercises, in terms of stimulus to fatigue ratio. Cadence was recently shown not to matter too much, anywhere from 2-8s per rep is fine. Further, strict form vs. cheat form seems not to matter much as long as one approaches failure.
Mike Israetel has preached the importance of slow eccentrics for a long time being more hypertrophic and as it turns out, not so much.
I realize this a bunch of nerd shit, but those genetic freaks that go to the gym and go balls out all the time are on to something. With these principles in mind, one really only needs to figure out what they can tolerate. I know I can't do max squats 2-3x a week. Not 5s, nor even 8-10 rep range and fuck a 20 rep squats. In fact, squats suck, but I still do 'em because they are the king of barbell movements, but...
Mitchell Hooper has claimed that a leg press was the key for his leg development. An actual strongman, one of the best, claims a machine exercise is superior to anything else is mind boggling. I'm an old man, but I can do leg press, leg extensions, and hamstring curls at least 2x a week and hit my desired 10+ sets per muscle group pretty readily. When I do, my legs grow like crazy.
Now if I could only get off my ass and work on my calves.