Cyclocross and MTB racing is one thing. There you have a chance. But for road racing SS just can't cut it, unless there are no hills whatsoever. I've tried keeping up with the fast group rides on a single speed and just can't do it, that's with 53/17 gearing. You need some serious gear when the pack is cruising at 30+ mph. Probably 53/15 or 14. I haven't tried that yet, I'm really not strong enough to push that kind of gearing all the time.