Ok, I was wrong about block rate going up. When I looked at my Canopus shield, the block rate is listed as 94, with Self-Presurvation I assumed it would raise to 99. However, the block rates listed are either totally wrong, or some monsters (not including enemies using magical attacks) have some way of ignoring or lessening your block rate. Either way, I think SE should look into the block rates and make sure they're correct.