I can totally understand and relate. This past weekend I almost ended up ditching off a trail and into a river (would've been a few broken bones or worse). I was riding on the SRT and came down a hill and around a blind turn (at about 12 mph) only to find "family hour" coming right towards me. 4 adults with 2 dogs on leashes and a little one on a bike weaving back and forth across the trail. I shouted as soon as I saw them, managed to avoid the child (barely - he weaved right in front of me but then right back away again) but I bumped into two of the adults. No one was hurt, except for me over turning my ankle trying to prevent a complete wreck. I was so furious, but bit my tongue. Sometimes there's not much you can do.

Personally, my pet peeve is when I yell "on your left" and get ignored by people walking abreast taking up the entire trail. So as I get closer I yell again and then they spin around only to jump (usually to their right / my left) and put themselves even further into my way. It tends to make me furious, but I just try to remember that not everyone knows "the rules" and at least they're out doing something. I just pray that they learn from the experience, though I suspect they probably won't.