There are different ways for players to learn boss fights.
- Trial and error. Go in blind, figure out what you can, and if you fail then figure out why you failed and try something different next time.
- As above, but with addons that give additional hints (eg. Change targets now! Move out of the fire now!)
- Talking to other players. Get someone to tell you what you have to do.
- Read about it offline or watch a video tutorial.
Blizzard have tried to incorporate #4 into the game with the in game dungeon journal. This lists out the abilities (and phases) of the dungeon and raid bosses.
Shame it doesn’t mention that the middle of the floor disappears in the last phase of the Elegon fight, so if you don’t run to the outside, you will die. You might think this was key information. I assume this is intentional to make sure that players need to figure out the strategy – but if it is meant to replace looking things up offline, it doesn’t work.
Do you find the dungeon journal useful?