Think of a baseball team - if they had a different group of players (strangers) every game, what would their average look like? Even if the team consistently had All-Stars on it.
A PUG Baseball team is going to demonstrate inherent problems. Baseball players spend months working together, learning how each other thinks, reacts, what each person is good at, and how to run plays together. They also learn weakness - when to compensate and when to replace.
You cannot have long term stable success in a PUG environment - it is not in the numbers and does not match to human behavior. I PUG 100% Need to find a group that plays my hours I guess.
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Family with young children, full-time work, etc... It's tough, I watch dumb things happen right in front of me. Other times I see amazing coordination, and we just steam roll. But, is it any one players fault? Hard to say objectively. How do I know if that person has 5 games or 500 under them? Even with 500, what does that really mean?
Frankly, I've done dumb things in hindsight trying to make a difference, sometimes it works and sometimes, I am a heap in seconds.
Guess my perspective is to enjoy the victories, learn from and then dismiss the losses, try to help team mates - focus fire, watch for opportunities to crossfire or flank, stay together.
Lights scout and harass, lure squirrel chasers into your team to get focused. Don't be a squirrel chaser BTW.
Meds stick close to Heavy/Assault. Heavies are the big brothers looking for opportunity. Assaults make themselves a target while hopefully making it hard to hit them (using environment, etc.) and responding with a lot of hurt.
Longer post then I intended...