noglider 

I think back to the beginning of this winter and asking myself if I wanted to use winter tires. I figured they would be overkill because we have enough days above freezing that we won't have much of the ground covered in frozen stuff for long. Boy, was I wrong. Not only do I appreciate these knobby tires, but given that next winter may be like this one, studded tires will come in handy. My situation is a little unusual for NYC, because my bike commute is longer than normal and because I take the Hudson River Greenway all the way to the northern end, which is so badly neglected. I was right that the street surfaces aren't so threatening, but I'd rather ride the bike path, and it's pretty useless to me now. Wednesday, I rode home taking the streets most of the way to avoid the icy parts of the bike path, and it's not a very pleasant route. Braving aggressive NYC traffic is invigorating but only for a few miles. After a while, it gets pretty tiring.

I really appreciate everyone weighing in, especially @cyccommute, @rumrunn6, and @Jim from Boston.
It was brutal. It took 90 minutes, which means the ice added 20 minutes. On dry pavement, when I looked down at my speed, I think it was around 13 or 14 mph.

Here is the record of my ride. You can see at the 50-minute mark, I was going nearly 0 mph a lot.

Now, here is a puzzle. In that very icy section, a guy came along in the opposite direction. Jogging. On the ice. Do you suppose he is super skilled, or might he have had studs on his sneakers? He seemed to be having no trouble, and his pace seemed only slightly slower than moderate. Not that I'm a good gauge of jogging speed.