As locomotor said, there is an inverse relationship between volume and intensity, and you can't separate them. There are some guys out there who pull one heavy set a week (or maybe even two weeks) and make progress, but if they were pulling 60% for a triple it wouldn't work. Higher intensity is better for building strength, but your potential for strength is limited by muscle mass. If you need more muscle then you definitely need more volume. You still need some volume for strength but the threshold is lower. You could say that enough volume to maintain muscle mass and still make progress is sufficient, but then the question is would you make more progress with slightly more volume? It's a bit of a balancing act because if you do too much then you will not recover. This applies to all lifts, just there are a lot of people who do well with lot deadlift volume.
As for Sheiko, the sample programs are all for lower level lifters. There used to be a sample of one of Yuri Fedorenko's training cycles, there were lots of singles at 90% and the intensity was much higher than in the sample programs. Sheiko has said that you need to progressively increase volume until you reach you optimal weight (based on your height, he has a chart for that) and then focus on working with heavier weights.