As the road meanders through the countryside, vegetation or buildings may keep you from looking ahead. You may then have a blind curve ahead for you: you cannot see any oncoming traffic, or even the next stretch of road.
If you’re on a narrow road when that happens, it’s not smart to stay riding side by side. If there is an oncoming vehicle, it’s a hassle to weave quickly. It’s much better to weave beforehand. You thus anticipate on possible oncoming traffic. If there is no oncoming traffic, it was a superfluous weave, but that’s no problem, right? Better be safe than sorry.
You give with signals that you want to weave. You call “Weave” or “Single line”. You can also give signals about what you want your fellow riders to do: ride before me or ride behind me.
In blind curves, you can also send a scout: someone who rides a few meters in front of the group and, when needed, signals in time. Those in the group will than have ample time to respond. The group must not catch up with the scout, as the group then looses valuable reaction time.
If your group wants to overtake another rider or group, it may be better to wait until you’re past a blind curve. You then have a clear view of the road.
Looking further ahead
When you encounter a blind curve to the right, it may be useful to start riding on the left hand side of the road well before that curve. You can then better see what comes after the curve. You must, however, be able to return back to the right hand side on the road quickly, in case that is needed. While you’re riding on the left hand side, it is important that no one starts riding to the right of you, as you will then be unable to return to the right hand side quick enough.