I was re-reading the USA Rules of Road Racing. Chapter 3B deals with Rider Conduct. Here is a Gem:
"3B10. Foul Riding. A rider near the edge of a road who leaves a gap sufficient for an opponent to pass may not suddenly close the gap upon being overtaken [relegation or disqualification]."
Bizarre little rule. I guess if you are not near the edge of the road, then the rules does not apply. How do you get redress if there is a 3B10 violation? If it were me, I would point out the rider that Rule 3B10 provides that I must be let in. However, I will say that my recent attempts to discuss interesting points during bike races with my competitors have had mixed results.
You can read the rules of racing in the USA here.