I'm sure it's possible with the right conditions, but that simply isn't the reality for most of us. And that includes facilities at the workplace, because if you average over 20mph on the way into work, you are going to be a completely sweaty mess unless you are some freak of nature with an abnormal body temperature maintenance system.

I ride pretty much as slow as possible in the morning, and take a ferry across the river, to avoid sweat as much as I can. But I don't put any restrictions on the ride home, since I will be able to shower and change at my leisure. This is my typical afternoon commute, which is obviously pretty urban. There is a traffic light at every single intersection on the Manhattan side, and although I skip 4-5 of them by using the 1st avenue tunnel, that's still over 30 lights. The only time I can really push is on the bridge, in the tunnel, and on a few small stretches in Queens. That 34mph blip is just a erroneous reading from the GPS/Strava.