That is scary. I've been in similar situations. The best I can say is to maintain constant awareness of when traffic is about to pass you. I can hear the approach pretty reliably. That helps you with quick situations where you know without checking that is probably safe or not. But always also do what you can to see an approaching tight situation and slow down (or speed up). Anticipated what you can. Be suspicious. It helps avoid surprises and the need for a quick strategy.