Honest answer, but still doesn’t explain why a group of bicyclists will spread out 3 and 4 abreast in an impossible to pass knot backing up cars other than the pure obnoxious factor. And as far as momentum at a light goes, when I’m driving it’s more fuel efficient for me to not stop too, but I do. Few things more annoying than having just gotten past a pack of road hogging cyclists only to have them squeeze by on the right while you’re stopped at the light, run it, and then have to face the task of getting past them again after the spread themselves out across the road again.
There are cliques of cyclists who hate cars, and make trouble on purpose. They get what they deserve.
My other bike is a 4WD, V8, Double Cab Tundra Big A$$ Truck.
;-)