This was proven untrue on my commute this morning. I had only a tiny 12" of shoulder to ride on, and I don't try squeezing myself onto a shoulder that small because some cars try to stay in the lane, and therefore drive too close to me. So I ride about 24" to the left of the white line. No motored conveyance with more than two wheels can squeeze past me without crossing the median.

And so it happened - A Special Ed. school bus, you know the short kind, crossed the median to give me room. :-)