Thing about Yates is he lies...a lot.
His training is never properly scrutinsed but instead is seen as some sort of mythical way of training when in fact it's just the pyramid scheme or a variation of it. It's based on the delorme watkins method which bodybuilders have used in various guises for many decades, since the 1940's in fact. It's nothing new or unique. Just one of the many different ways to train that's out there. Yet the hit cult think it's something magical and praise it as the only way to train. It's not and never has been.
Yates, like most bodybuilders, used different methods to build up. He used pyramid sets, straight sets, reverse sets and drop sets to build his body. Let's not forget the fact that Yates did weightlifting and powerlifting along with martial arts in his teens so he already had a good foundation to build on when he took up bodybuilding at 21. He used traditional methods to build up and not hit.
His old chest routine from the 80's was this
Bench press 135x10 200x8 265x8 285x7 310x5 pyramid sets
Incline press 250x5 240x5 230x5 reverse sets
Incline flys 70x8 70x7 70x6 straight sets
Source: his 1985 to 1990 journal files