Originally Posted by
350htrr
I think it's definitely improbable. Averaging 21MPH is pretty hard on a legal E-assist bike...

JMO
+1 but for a different reason.
There's always lost time in any urban commute. A few minutes lost to red lights, backed up traffic, or simply to enter a busy intersection. Making up that lost time means needing to maintain much higher than average speed for the moving part of the trip. Of course, with a bike, one can maneuver around delayed traffic, and break a few laws, and maybe make the trip in 20 minutes, but not if the top speed of the bike is limited.