I'm not really keen on the science. I couldn't possibly hit quads twice a week with the intensity that I put into each workout. Squats, Hacks, Leg Press, Extensions, Lunges. My Legs are torched and take time to recover from that amount of volume and intensity. I can recover enough for hamstrings later on, but honestly it sounds like your full body split is more lazy and hippie oriented than anything I've outlined and execute. Please stop posting scientific garbage in my log.
It seems that way until you actually do it. Granted, "training quads" isn't the same thing (in terms of intensity) as squatting. You probably don't want any higher than 20 sets per week of actual squats. But your legs will not be as sore if you just force yourself to work them repeatedly.
"Scientific garbage" -- Lol! Science isn't garbage buddy.
Muscles do not grow any longer than 48 hours after training stimuli. You're missing 5 days of potential muscle growth by employing that shitty 90's bro split. They're also fully healed after 48 hours. DOMS is not indicative of growth, healing, or anything remotely useful.
If you only squatted 5x5 3 times a week and added 5 lbs every session, you'd get far more hypertrophy, actually end up with good squat form (which I guarantee you don't have now), and get stronger in two weeks than you will through out your entire cycle. BTW, quads are mostly comprised of fast twitch muscle fibers, so they respond better to lower reps than higher reps. Blasting all of those random exercises at high reps is just silly.
I guarantee you're that guy squatting 165 lbs with his buddy, in a hoody, with your Beats by Dre on, and glancing sidelong at the 150 lbs kid doing 365 for paused reps after he waits on you to finish up. The funny thing is he's probably natty.
And this is where I find the mentality of someone like you hilarious: You're willing to risk your health with less than intelligent use of AAS, but you aren't willing to work hard in the gym. So many steroid users look like shit, because they never learn how to actually train before cycling.
Do what you want man, but science isn't garbage. And in 3 years when you've failed to maintain the bodybuilding lifestyle (and don't even have a cumulative total of 1 year in the gym), I'm sure you'll do a similar cycle, while guys that take it seriously won't even need to.