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xkcd #2932: Driving PSA
(imgs.xkcd.com)
Alt text:
This PSA brought to you by several would-be assassins who tried to wave me in front of speeding cars in the last month and who will have to try harder next time.
I've got several years of experience riding motorcycles. It's taught me to read traffic. I see a gap in a line of traffic like that, it's either a driver who's smart enough not to block an intersection (rare), or someone letting another someone out.
When I saw the gap I started watching it closely. I probably wouldn't have been able react fast enough otherwise.