Discussion value stems from the ability of a topic, singular in nature, to spur conversation between users on said topic. If a thread doesn't develop conversation between all users on a topic, where users can actively engage one another and converse, it doesn't have discussion value. Therefore, an AMA thread for example, doesn't promote discussion between all users in the thread as it instead promotes discussion between a question poser and the original poster (something more suitable for private messages or instead hold an AMA in groups). Moreover, it is inherently topic-less, relying on future users to give it a grounded topic. Obviously, these are just my opinions on the matter. And, I find that OPR is right. The man is Gandalf and wise beyond his years. Threads without established topics for discussion tread into grey areas and ultimately tend to devolve into conflicts, harassment disputes, and general ugliness. [Edited on 12.22.2012 7:59 PM PST]