When I maintain gaps, it's not empathy; at best it is a smug feeling of maintaining a better risk management profile than the person deciding to cut.

I long ago gave up viewing driving as an adversarial activity. Slamming on the brakes means I'm not maintaining a safe distance or speed. Any pent up frustration or anger I harbor is reserved for the sap that caused the accident up ahead that slowed everyone down in the first place.