As a person who can see both sides of the argument, i'll try to keep both in mind as i type this. On the one hand, if you had two hours free time before you had to go on with your life, would you want to have to constantly repeat something for little worth just because one person keeps on messing it up? Especially when these are people you have next to no chance of encountering again. When they seem determined not to learn and to fail. But then again, there is nothing better then pulling somebody through the raid, who came in not knowing his Warpriest from his Golgoroth. To leave them with the memory of how they learnt how to do this raid? Provided people are willing to learn, then this can happen easily. In the end, there are those who do not want to learn or have not learnt, at this point in the DLC then it is rather scarce to find somebody in the first bracket for normal mode.