There’s a simple way to survive that daunting situation when you overlap wheels with the rider in front of you and his rear wheel is bumped:  Turn into the direction of contact. This means that if your front wheel bumps the rider’s rear wheel on your right side, turn your handlebar to the right.  This provides a counter force that pushes you and the bike away from the rear wheel without losing your center of gravity. In this technique, your entire body and bike will act as one solid unit and be more likely to bounce off rather than jackknife into a crash.   Since the rider in front of you has all his weight on the rear wheel, it shouldn’t affect him too much and the consequences won’t be much more than a nasty look.  You can practice this technique on the grass with a friend riding in front of you before taking on the road.