Power, weight, climbs, descents and speed

Yesterday I had a super interesting ride on the road with a friend. Nice ride with a couple of long climbs, 5 miles and 8 miles long. We rode side by side for most of the ride, with no drafting. My friend weighs 75 pounds more than I do. On the climbs he was working harder than I was for sure but on the descents I had to put the hurt on myself a little bit to keep him in sight. I notice this on group rides. On descents if I'm tight in the draft I can stay in but if I get pooped out into the wind it is all over. I wasn't drafting on the descent yesterday and was dam near threshold at times just holding the 50 yard gap constant. Once on the next climb it was back to me spinning easy and him working harder. I was wondering if he hammered the descent or it was really the weight that made difference. Well we were both riding Power-Taps so I was able to look at the power profiles side-by-side for the real answer.

On both climbs my power average was 145 watts and IF 0.654 and his was 204 watts and IF 0.888. On the descents I averaged 160 watts and IF 0.726 and he averaged 147 watts and IF 0.641.

There you go. I did bust my butt on the descent.