You don't have to be a slow rider or a klutz to take advantage of a tandem on rides like TOSRV or RAIN. Far from it. There have been a lot of 25+ mph double pacelines on TOSRV with tandems taking the first wheel on both sides. Most of the fast tandems that I have ridden with prefer to lead anyway, since it's difficult for a tandem to moderate speeds in a paceline with singles. I drafted a tandem for 60 miles on RAIN and kept up a running conversation with them while going 25 mph. They were glad for the company and I was glad for the tow! But, if your nervous about it, just say so. This isn't limited to tandems BTW, We've had up to 50 riders drafting us out of Portsmouth on TOSRV on our singles. The real problem in pacelines is recumbents. They take up a lot of room and provide no draft, so it's useless for them to pull. I don't know why they get in pacelines anyway since they have a tremendous aero advantage.