Great topic. Just want to jump on the "got to put in the work" theme.

While it is true that we can get a bit faster just by riding and keeping at it - it is truly amazing what just a little concentrated effort can do for your speed.

The trick to getting faster obviously is being able to ride harder for longer and one of the best ways to learn that is by doing one or two interval sessions a week. The interval session just below, at and above your LT will help you get more comfortable going harder and help you recover faster - which (at least to me) is one of the keys to being able to survive the constant surges and attacks in a fast group ride. I know everyone is training with Power Meters these days, but I can't afford one so I still use Heart Rate for my intervals. NOTHING helped me get faster ... uh, faster ... then intervals - including the hill repeats RoadRaven talked about ... AND...

Riding with people who are faster than me - especially if you can organize rides with people who are faster, but are committed to riding with you - and basically stopping every so often so you can catch up - not easy to find, but if you can do it, I recommend it because that way you don't just get dropped once, you get dropped and have to chase like twenty or more times. The trick is to keep chasing - don't give up. It took me a long time to listen to my husband who sounded like a broken record "ride with faster people, ride with faster people" but doing exactly that brought me from a 11-13 average to being able to do 21-24 in race and 15-19 on my own. It was really hard for me to get there, but it was so worth it.

Of course, if you do this kind of training, recovery is even more important - one or two monster efforts a week and then ride slow. A lot of coaches say that one of the biggest mistakes cyclists make is not going hard enough on hard days and not going easy enough on easy days.