I have a road bike I commute on, but not the road bike, if you know what I mean. I use a steel beast (relatively speaking - comes in at 25lbs which isn't actually that bad. It is also easily the best looking of my bikes - when it's clean.) of a road bike that I've installed fenders and a rack on. It has downtube shifting and a compact double, 9 speed drivetrain. Very reliable, very solid. I've found that commuting miles are hard on bikes, probably because you are out in really bad weather at times, you are out nearly every day, and you don't have time to baby the bike between rides.
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --
the tiniest sprinter