It’d be one thing if the dungeon didn’t need a guide, and you could just select it and not have it affect your queue times. But everyone and their mother is going to select the Dungeon Guide option because it helps their queue times.
Blizzard needs to rework how this works, to at least not give any sort of benefit to people who select it.
Oh that’s interesting. I never knew that it helped the queue times. I usually queue it alongside tank.
It doesn’t.
It just tells the system you want to be marked as leader.
There is no benefit other than that.
Well, I’m back to where I started! 
thank you for the counter point
Honestly if you queue tank or heals, you should only be waiting 2-3 minutes on average.
I went from 25 to 60 in a few hours on my shaman last night from healing queues. Most were instant. My longest was 5 minutes, but that was one of my last ones at 5am 
I select it cause I’m an opt in guide so dungeon guide also seems legit. Also party leader has a higher chance of being the phased server. Welcome to my oceanic ping.