Out on a 16mi. tandem ride with wife/stoker yesterday, trying to work up to the Hilly Hundred in October, spied a young fellow on a lightwt. road bike ahead of us. Of course, couldn't help it, picked up the pace a little and, sure enough, passed him ("howdy") and then dropped him. You can do that on a tandem on rolling terrain; two 50+'s can pass someone on a single who is younger and likely fitter. On downhills, get outta the way! Worshipping the god of gravity. Don't ask about climbing hills.