Guys that are fast off the floor legitimately don't like deadlift bars because of the whip. No amount of practice will change that.
I find the claim that increasing the rom ~1.0" and decreasing the rom ~0.5" both add lbs to the lift to be incompatible.I'd say there was a difference between choosing to wear Oly Shoes to allow you to pull what would be a stronger style (for the individual lifter) than unilaterally changing the bar height for everyone...links back into where the individual lifters weaknesses are, as you correctly pointed out above.
Decreasing ROM seems really overrated. Being able to get into a better (tighter, more open hip angle) start position matters more. Seems like this is easier to do when using a more flexible bar. Kinda like having slightly longer arms.
Remember though, the .65" is if you are pulling right in the middle of the bar. Even with a closer grip using conventional, you won't be anywhere near that. Some sumo guys get closer to the middle, but I have never seen someone pull right on the middle of the bar before. And guys like me, who have my hands just inside the power ring, see way less than the .65".
I am not sure. If you look at my most recent video, not much I would say. For me, pulling with a normal bar isn't really much different. I just use the deadlift bar because it is in a lot of the competitions I do. Also, I keep it locked up, so it isn't bent at all.
You are correct. He would be one of the few exceptions to the rule.