No, block gets pushed off the table first, yes the higher % you block the more likely it is for a block to occur, however the tradeoff isn't going to be with dodge/block, it would be with getting hit vs. block if anything.
So lets say:
5% natural miss
So you're roughly 20% away, Holy shield is what, 35%? So you're gonna be sitting at 40.4% chance to block, and increasing block isn't going to increase that since you're already unhittable, since block is pushed off the table first, the only way your % block can go up is to drop dodge/parry/miss.
I don't think I'm explaining this too well... do you follow me?