>>59165561A good example is the big lunge he does
You can easily get psyched out by the timing because he holds back before hitting, but if you dodge to the side he misses and you get free hits
Dodging puts you in a better position to punish, while p-blocking builds the boss's invisible stagger bar (as does hitting, and charged R2 attacks even more so)
So if you're using, say, a sick greatsword then you dodge big swings and charge and slap while guarding big multi-hit combos because you can feather the block button to p-block all of them