Even many of John Forester's harshest critics acknowledge the merits of the sections of his book,
Effective Cycling, that deal with lane positioning. The rule here is simple:
If the lane you're in serves multiple destinations, then ride in the part of the lane that corresponds to your destination.
In other words, if the lane serves N destinations, then ride in the "Nth" portion that serves your destinations.
Specifically:
If the lane serves two directions (say straight and right), then mentally divide the lane in half and:
- if you're going straight, then ride in the left half.
- if you're going right, then ride in the right half.
If the lane serves straight, left or right, then mentally divide the lane into
thirds and:
- if you're going straight, then ride in the middle third.
- if you're going left, then ride in the left third.
- if you're going right, then ride in the right third.
This is essentially what Forester means by "destination positioning", and is just as appropriate for motorcyclists as well as bicyclists.
The reason it works is because riding this way improves (but of course does not guarantee) your conspicuity and predictability.