Block reduction

"After 10th round, battle fatigue will also kick in for PvE (lose 1% block rate per round)"
So, is this apply in the boss fight as well? If yes, this would be unfair for us sword users. We just got additional 4% of block from the new class while the magic users got +32%, now, by applying the battle fatigue in PVE you made it even worse.
So, is this apply in the boss fight as well? If yes, this would be unfair for us sword users. We just got additional 4% of block from the new class while the magic users got +32%, now, by applying the battle fatigue in PVE you made it even worse.