Last night we attempted to farm riverside 4 times. Only the first try yielded any unlocks (I got major inspiration and minor something or another, and somebody else got a minor rune). I noticed there are a few stragglers who hang out there looking for groups to abandon and run straight to the hill giants (to escape anti-farming code perhaps?).
I have also noticed that when I do get color-named drops, I get more than one (usually between 3 to 5), but I have never just gotten ONE from a zone.
I am beginning to wonder if this is anti-farming code. It seems that if you go to the same zone with the same group you wont get good drops, but if you change groups you will. Can anybody else present any evidence to support this?