True...but had Vince trained any lighter, he would have been using the link dumbells.
He was an incredible responder. Realistically, Vince could have taken gear, ate junk food, and not even worked out, and looked like a top amateur competitive bodybuilder - if I had to guess.
His training was...like watching a woman train.
Watch his 2006 Battle for the Olympia training segment.
https://www.dailymotion.com/video/x1mmzdHe was around 50 in these videos. What do you expect him to do--lift like an animal and beat the logbook? He's coming in and getting a pump, training the target muscle and letting the drugs do the work. A pretty smart way to train when you're juiced up with prime genetics, let alone at age 50.
On an aside, the one arm pulldowns he does at the start with the hammer strength pulldown machine are a GREAT way to hit your back. Really isolates the back muscles, takes the arms out of it completely. Give them a try, they're good for a great pump.
E: I forgot he was using 3 plates per side on the modified pulldowns. That's pretty strong, considering he goes for 20-30 reps/set.