In view of certain recent situations, maybe it's time to refresh memories and update this.
Other stuff not really addressed by the other posts.
When there is heavy traffic, go with the flow of the traffic. DON'T treat the heavy traffic as a slalom course. If you do ... there will be phone calls from cagers, and you might find the po-lice out looking for you. Not good. The entire group should follow the flow of traffic. That includes both the leader and all of the followers.
Never, ever, EVER, pass another bike in the same lane, except if the first rider motions the following rider to pass (which means the lead rider is aware of the following rider's actions).
Don't ride side-by-side with another bike. If either one of you spots a rock or pothole or oil slick or whatever, then you are probably both going down, instead of both having an escape path.
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