Happened yesterday, in fact, and I was going faster than the traffic flow and exceeded the speed limit by 10-15 mph. The guy (likely Medute in his red pickup truck with oversize tires) was uncomfortable close, so I increased my speed to about 20 mph over the limit until I got to an "exit" area from the carpool lane (here it's all double lined until you approach exits). What exactly was I supposed to do, short of going 90 mph on a city freeway?