Honestly what kind of mystical mmo's have you been playing?
I come back from some wow time and in dungeons people don't care if you are new or anything, they just rush ahead. Hell you would be lucky if you even get into the bossroom cause you are typing you are new.
Then raid wise there is LFR which is the closest to DF there is there and since mechanics cannot kill you unless you stand in the fire 100% of the fight nobody cares.
Oh and i just came back and did my story from 2.4 to HW and explained i was new in every dungeon/trial and i have never someone yell at me to watch a video.