My route to/from work involves filtering past literally hundreds of cars every day, and there are several sections after traffic lights where I'll constantly get stuck behind someone doing 40mph in a 60 zone, with limited opportunities to overtake. Round here no-one, and I mean no-one drives at the speed limit in NSL sections, let along over it
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40mph in a 60mph? Yep. 50mph in the outside lane on a 70mph DC? Oh yes.
Granted, there are certain lights where there's normally only 2-3 cars in front and sometimes I won't bother filtering past them, but most of the time if there's time (knowing the light sequences) and space I'm to the front, and ready to go.
This is a normal ride to work for me, but you'll see I don't
always filter to the front