I've seen quite a number of dogs up at Prospect Hill. Roughly a quarter responsibly managed/contained, walking fire trails, half walking fire trails, but dogs roaming all over the joint, and a quarter on the singletrack. Those ones really shit me, because they are invariably spooked by someone flying into their little playground, putting both the dog and rider in great danger. Owners either berate me to SLOW DOWN, or casually remark, don't worry, s/he's OK. No, the dog that I almost ran over, if not for extreme evasive action, and pure dumb luck is not OK.
I really like seeing dogs get to enjoy this area, but the number that are well trained, and under control is small.
Just as dickhead roadies give all roadies a bad name, and endurobro's give mtbers a bad name, ignorant, selfish dog owners give responsible dog owners a bad name.
As others have said, it's not the dog, it's the people.