Elon Musk views any human user intervention is an error situation for the Tesla Autopilot. Elon means that whenever a human has to take control from the Tesla Autopilot system this is indicating an error that must be fixed for a future fully autonomous car.
Currently, the autopilot does not recognize stoplights. A regular autopilot user will perform a fair bit of adjustment of the maximum speed and how much of a gap to leave during commuting. The system has can mostly handle on-ramp to off-ramp highway commuting.
It can still be a fair bit of work to monitor autopilot to get through the lane changes to get to the HOV lane.
SOURCES- Youtube, Elon Musk
Written By Alvin Wang, Nextbigfuture.com