I only walk when its cold (its too hot to walk in the morning now so I take the bus), but I kind of walk fast. My office moved and is now 3 mils from my apt and it takes me 33 mins to get there but at 2 miles it took me about 22 mins.
I also dont really get cold in my torso area its my hands (due to really poor circulation)
It sounds like you walk pretty damn fast. When the trains were down here after Sandy, it took my about 40 minutes to walk 2.75 miles and I consider myself a fast walker too.