Tonight after work I did another cold training ride (around freezing) on my studded-tire mountain bike, which weighed in at 44 pounds on departure. I did 50 miles in about 3.5 hours and hit a variety of hills with ~400-500ft elevation gain each, one of which has a couple 18% grades.
All things considered, it went pretty well... I was munching fig-bar cookies and drinking some energy drink, and could've thrown on one final 450ft climb on the way home, but it was already 10:30PM and I have to work tomorrow. Plus my feet were cold.
http://app.strava.com/activities/3960331
Now I can eat pizza 100% guilt-free