Originally Posted by
wxmcpo
I did manage to ride a 17.2 mph pace for mile 25 miles on Saturday and then 16.9 mph for 45 miles on Sunday. I know that's no where near serious competitive cyclists, but for me it is pretty good and hopefully I'll keep improving.
Nonsense! Just add some mandatory BF Average Speed Inflation and you're ready to go pro!

In all seriousness, "on your left" seems like a MUP formality, and I have never had anyone say it to me while on the road, but I realized on a ride the other day that it's better than saying "hello/hi/howdy" as you pass them. I was passing a rider on Saturday and planned to say "Howdy"* when he started to change lanes to make a left turn when I was next to him but out of sight, and he just saw me and got a little startled.
*I almost always say "howdy" to everyone I pass, but I NEVER say it in off the bike, and I don't know why.