Steve, different strokes for different folks I guess.
I've never done block pull deadlifts, however, I can clearly see that lowering the block, over time, would make one stronger. It's another form of progressive overload, the weight is not increasing but the range of motion is.
Towards the tail end of a peaking cycle, I like to do heavy deadlifts (at or even above 100% max) with chains. If I were to fail (I don't actually fail, FYI, only in theory), it is not on the floor, but actually right below my knees (a few inches from the floor). Overloading with accommodating resistance forces me to be more explosive (I'm a Grinder, by my nature) to blow last my sticking point. It also builds confidence when I do lift a max weight (knowing that I've lifted more than this before).
After a heavy deadlift with chains, then I like to remove the chains, drop the weight down to 50 or 60% of max, and do deadlifts where I pause right below my knees (2 sec count or so).
Carl, I like deficit deadlifts too. However, I don't do them as often anymore because i struggle to maintain my same regular deadlifting form. I find that it becomes a different movement for me (like sumo vs conventional). It's not a bad thing, I just avoid them when aIm peaking.