The biggest part of PvM in this case is understanding any sort of spawning and attacking of monsters. You need to know whats going t hit you for the most DPS, where / how / if you can block things, what to pray on, what to use different styles on, so much comes into play. Understanding the mechanics of the different monsters will really help. If you spend tons of time watching someone else do it, it'll be easier for you when you do it.