I would imagine that there is some form of oil circulation going on, otherwise top end wear would be rife with it shutting everything down in stop start traffic.
Good point, I aint killing my engine to kill my turbo after doing traffic light GP immediately previous to the traffic jam

It is also a dream of mine to have a large engined car and sit in traffic with the revs at the red line. I'll sue if they ruin my dream, or invent humps in the road that damage my suspension.