If some random rider latches on, I'll point stuff out until either the rider goes by, turns off, or drops off. I'll ease my pace unless I'm time-challenged (like I have 3 hours left to ride and it's 2.8 hours until it gets dark - this mainly applies to North County "training camps" since that's about the only time I do regular long rides).

Having said that, although I point out stuff, my expectations of others is much lower. I assume they won't. Therefore I always ride like I do in a race - look out for my front wheel and keep an eye out for any potential problems.

When I'm out there in Feb I'll post something somewhere. We can go for a nice, friendly, etiquette nice ride.