When two cars are laterally overlapped and longitudinally close, the sim enters a side-by-side state that’s resolved at the next braking zone. The cession protocol prevents cars from being stuck in parallel for a full lap (a problem in earlier builds).
This page will document the full attempt → commit → resolve flow, the off-line attrition penalty, and how aggressive vs. conservative drivers behave differently in side-by-side states.
For now, see Overtake Push for the toggle that biases attempt rate.