I just spent 20 minutes getting to the first boss of DhT in a +4. I joined a group that was called “DhT +4 , 3 Chest” and in the description, it said “880 Tank, 870+ in group already”. I’m an 885 WW monk, so I thought it would be a smooth run. They summon me, and as soon as I walk into the dungeon, they start the stone. We wiped on the second trash pack.
Then, I inspected the healer. It was a 785 holy paladin in quest blues. Then I looked at the tank and other two dps. The tank actually was 883, but the two DHs were both in the mid 840s, and were doing about 150k dps. The healer and demon hunters died countless times before we got to the first boss, and then once we got there, the tank pulled without one of the dhs and the healer, so we wiped again. After that, there was 16 minutes left in the dungeon.
Don’t lie in the group finder. And when you join other M+ groups, inspect people beforehand.
EDIT: Here’s a screenshot of the healers armory page