Today I've seen a Mentor hovering right in Front of the Quest Giver from the Beast Tribe at the Ruby See so you couldn't see the Quest Mark. He stayed there for at least 3 Minutes (till I left the Area). Good Behavior for a Mentor, no?
Yesterday I was doing Potd with a Mentor Dark Night. He died twice from the Tornado at the 70-80 stage Boss, he just wouldn't move out of the Aoe even when he was told to do so.
There are more stories similar to those.
I've come to the Point were I'm thinking that Mentors are the most inconsiderate, most arrogant and most incapable Players in that Game. I have no respect for them.