Hey, some of those were the idiots I saw on the trail!!!

There's nothing wrong with going slow down hill. If it makes you feel better, put your right hand straight down and say "SLOWING" and slow down. People can and should pass you, there's NO WAY that 30 people can all go down a hill the same speed and maintain a single line.
The way my group does it is we pretty much each go our own speed up and down hills, and regroup at the top or bottom.

REmind the leader that people are going through stop signs and or passing inappropriately (on your right!) because that will encourage THEM to remind the
rest, hey, if you can't do this right...

You must have passed us. what color ribbons are you guys wearing?
mimi