I am way too lazy and stoned to read all these posts, but I will post my experiences.
I have gotten some good and some bad clones from the clubs. Some of the worst weed I ever grew was Purple Kush from one of the clubs. After growing it and seeing how shitty it was, I said fuck it, cloned it, and sold the clones back to the club.
I have also gotten some awesome Purple Urkel, which I still have around, Trainwreck, and G13xHashplant. Now while I have gotten these 3 awesome strains, I have had a few average strains as well.
I will agree that some growers don't put out their prized genetics, but usually they are not putting out the "runt" as it was called. You are probably either getting a renamed cut or some one bred the strain themself and it wasn't very good. Like if some one is selling blue berry crossed with say white widow. They don't do major seed runs like seed banks do in order to pick mothers and fathers, so the offspring may not be as potent. They grow out these unstable seeds, and while they are what they say they are, they are just not bred correctly.