Originally Posted by Helmet Head

Seriously, the reason I take a centerish position away from the margin space on the road whenever possible (including whenever same direction faster traffic is not present) is much more about being better positioned to deal with potential hazards in front of me (improved sight lines to/from me, larger escape/safety buffer to the right, riding in a more conspicuous lane position, etc.) but I do feel it also helps those behind me to be more likely to notice me up ahead, and be less likely to choose to attend to a distraction, and be distracted, as they are passing me 10 or so seconds later. But that requires me to monitor periodically and regularly to the rear with my mirror, so I know when to pull aside.