The issue isn't "randomness'. The issue is ANONYMITY. Even if you just cobble together pepole off of LFG sites. There is a level of investment by those people...and the possibility that they might have to come by you again in the future in order toget a chance to play. So they are going to be FAR less likely to act in disruptive ways....and much more likely to stick around and work out any problems. Rather than just up-and-leave. Case in point: I"ve NEVER had any problems with team mates in Nightfalls, or in the Weekly Heroic before it went to matchmaking. Want to guess how long it took me to run into people who are terrible players and couldn't clear the strike, because they kept dying every few seconds? First week. Want to know how long it took me to run into such a determined GRIEFER that I actually was forced to quick th strrike? SECOND week. What to know how long it took me to run into a random in the PoEs that up and quit on us after we wiped two times on one of the hardest encounters? Second week.