Decending on my tourer is much more fun than going down the same road when racing. I could certainly get round the bends faster on my road bike, but the extra weight makes the straight faster and the bike feel more planted. More importantly though, a decent when racing is about how fast you can go, how much risk you are prepared to take, how scared you are willing to be. Coming back down the the hill on a tour is about... WEEEEEEEEEEEEEEE!!!!!!!!!! if you want to slow down you can. If you want to stop and take a photo, all you have to look forward to is more WEEEEEEEE!!!
I love going down hill when I tour. When I used to race? Not so much.