I have run almost every dungeon there is and a 100% FACT is that the NPC’s arena net puts in these dungeons are more of a pain in the butt than a help at all. So until you can get them to work CORRECTLY just take them the hell out. My gripe comes from 2 things with them.
1: They bug out! Not all the time but in EVERY SINGLE instance where you have an NPC a long for the ride, I have experienced them not working correctly. And hindering getting the final reward.. you know how pissed off that makes people.
2: NO I DONT WANT TO TALK TO YOU! Get rid of the friggin option to talk to the NPC once the story is going. The last thing I need when im focusing on trying to dodge a 1 shot ability from a boss, is a that blasted NPC green bar on my screen asking me to talk! it gets in the way of all your interaction buttons and your looting as well, just get rid of it!
I pray to the heavens above that some dev reads this… its annoying the living hell out of your players.