Any training system will work to an extent. There are pro's/con's to every method. I trained high volume for years and still do from time to time. It all works. Common sense really but if you combine intense sets and high volume you need to make sure you can recover effectively. I have never believed in going to the gym and not pushing the intensity so this is why it's important to cycle volume. It's also important to know when to have a break even if that's just 2 days. It's quite pointless going to the gym and training for 2+ hours and just doing shitty sets all the time. Sure it's better than no stimulation and you could still build a good physique but some sets need to be pushed for optimal results imo. The other side of the spectrum is abusing your body and pushing it to the limits and that is the side I am just naturally on and that can go against you but if you know when to have days off and rotate intensity it can still work out great. Others just push and push with no off switch and that's why they end up with 20 different injuries and fucked up bodies.
I see this guy in the gym and I was going to post about him in another training thread but I may as well post it here. It was basically to show so many overcomplicate training. Although I should mention what I see him do is far from optimal and I would never recommend it. Digging a hole too deep is hard to recover from and he could get the same results doing 1/2 volume but still I will post what I see him do. I have seen him train his arms a few times. He will do at least 30 sets of heavy curls all to failure. I warmed up slowly and I done about 7 exercises and in all that time he was just curling db's or an ez bar so not even tri-ceps just bi-ceps and forearm work. Want to know his best body part... his arms
Obviously I would never recommend someone train that way but you have guys afraid of doing more than 5 sets and go on about RIR to prevent overtraining and this guy has a great set of arms and is literally just doing ridiculous volume and this is like 1/2 the workouts I have seem him do. It should go without stating he could just have good arm genetics but it's definitely a bit of both and whilst it's completely unneeded people shouldn't be scared of a little volume from time time. The way I look at it if you like to train and see a routine you want to try just try it and see how you feel regardless if it's 5 sets or 50 sets.
500 reps to me is nothing crazy especially because they are not to failure. Go in the gym and pump the fuck out of the body part and take some sets to failure (or close to) and that will be a good workout. Although I would personally listen to your body as opposed to just following a set routine and when your pump starts fading that's when you know it's probably time to go so finish with one big set to failure and rest and recover.