I just got out of a dismal Steps of Faith run. I gave the bulletpoints. DPS on cannons, someone on Dragonkillers, don't fire 2nd killer till after you fire snares. Someone asked how cannons worked, and I said "Same as Vigil Hard". People wouldn't volunteer to take cannons or Dragonkillers, and DPS was awful.
I got annoyed when someone, AFTER the wipe asked "What are snares?" If you didn't know, ask before the first run. A Steps failure is 15 minutes out of my day for no reason.
I told people it wasn't my job to explain every single part of the entire duty. (Please note, I had tried my best already, not everyone is gifted with the ability to really teach something.) At which point I was told to "Man up and explain it, because you are the tank". Note, the OTHER tank wasn't getting any lip.
Why is there a notion that Tanks should be the Mighty Walking Strategy Guide? I can respect someone saying "I want to go in blind" and then playing blind. That is their right. I don't fancy being expected to explain fights. If you want to know what to do without figuring it out yourself, watch a guide. Don't EXPECT someone to explain the fight. Especially don't expect it and then complain that their explanation wasn't good enough.
TLDR:
No where in the job for tank is "Know and explain any duty someone doesn't know."