This is an interesting thread. It really puts in focus how different we all are and how different ride styles/paces are so individual. On a ride as you describe (I have a similar club ride) I will average 15-15.5. I can do 23-26 mph on the flats but suck in the hills. It's not that I ever feel like I can't make a climb it's just that I'm slow. I attribute that to excess weight (187 lbs when I should be 175 lbs) and age (66 in June). It's always the hills that drive my average speed down. In a big way. The idea of getting better on climbs yet not getting faster does not compute to me.