My friends and I have helped many people with raids that were just on the cusp of being where they needed to to actual attempt it easily. We didn't mind, a d offered up advice if the people asked. But that was finding people in LFG. Matchmaking, that's another story. I feel like a majority of the time, people in matchmaking don't care and just want to be carries. Prime example, my buddy was doing the heroic weekly last night and he ended up with 1 person from MM because I couldn't get on in time to run it. Right when the new guy gets to the priest encounter, he runs in, goes under the cave where the drew spawn and dies..... you could tell he did that on purpose because he only has 15 total kills at the end of it.