Just going back to the discussion on page 1...

When I first got on a bike, I was obsessed with my average speed and how to make it better.
As I got more experienced, time on the bike became more relevant and useful and my average speed an interesting statistic but not a goal...

Pedal Wench, Geonz and Eden have hit the proverbial nail on the head.

Averages are only useful in terms of measuring your performance over the same or similar course/s. If you zip over to BikeJournal and look at one of my months, you'll see that while I race at an average speed of somewhere between 27-32kph, most of my rides are under 26kph average.

If I am doing hill reps, my average for the ride will be under 20kph, and yet the power output and intensity of the ride will be much much more than when I do a recovery ride on the flat and average 25-26kph.

Regarding joining group rides...

Our club gives suggested averages for each of the six grades...
For example, the beginners grade (G) often has a winning/finishing average of 28-30kph over a 17-20km course while the top/elite grade (A) often has a winning/finishing average of over 40kph over a 35-40km course.