I've ridden tens of thousands of miles on bikes, solo and with large groups. When I come upon a cyclist on a one-lane road that is winding or otherwise tricky to get into the other lane, I slow behind the cyclist until I know he/she knows I'm there. I can then tell if they know what they're doing. If they know what they're doing, they hold their line and I can pass with as little as a couple feet. If they don't know what they're doing, I get at least a car width room before I pass.
On a motorcycle, no need to even slow down. Just move to the left of the lane and keep rolling.
1974 R90/6 w/1050 kit
'91 Bill Holland Steel w/Dura Ace