OK, so first things first. Keep in mind that im not a coder, so i can just look at documentation and discussion. Since other sources have confirmed it, ill take your word for it that this is doing what you say its doing. But heres my take and why I wasnt sure to begin with and still have my doubts.
So used.power is like fuel to assign rshares. And vote_regeneration_per_day is like how much gas gets put in your tank every day.
So in the current system, say a 100% vote is like using 1 gallon of vote.power fuel to assign 10 Rshares. What you're saying (which though it might be true, is not clear from documentaion or discussion) is this
under the new system, for each post you vote on, instead of consuming a maximum of 1 gallon of fuel to assign 10 rsahres, you will be able to consume 8 gallons of fuel to assign 80rshares
This might be true. I certainly can't prove it isnt. But based on what little information i can find in plain english on github, the following scenario could also be true.
under the new system, you will be able consume 8 gallons of fuel at once, but that 8 gallons will only give you the ability to assign 10 rshares.
Now maybe there is some essential link between consuming used.power that makes it so that consuming a specific amount inherently generates more rshares. But its not obvious to me. In the spirit of full disclosure my interpretation of the change in vote power consumed has been the second thing, so if its really the first at least part of my reasoning was wrong.
You know that I already believe this, but from my reading of the code, I'm 99% sure that it's the first of your two options. I'm sure enough that I'd unhesitatingly bet money on it.