[Sportsandrec] Multiple shifters on tandems

[Thornbury, Kelly]

While I would probably like the idea of putting the shifters in the stokers hands, the rear rider is at the disadvantage of not being able to see (whether sighted or not) upcoming terrain changes as well as the captain. Also, so many bikes today use the integrated brake/shift levers, which just leads to more work to move them back and forth. If I end up with a captain who isn't real familiar with shifting, I avoid going for the hard hills and high traffic areas until we become more comfortable together. 
As for giving both riders control over shifting, I don't expect this will ever happen. With cable shifters, this would be an engineering nightmare, and each rider would only be able to move the chain to the next larger cog...front or rear, and both riders would have to shift to smaller cogs. It would simply be much easier to talk to each other...it is allowed when you are attached at the seatpost you know. 
I have ridden touring tandems where the stoker had control over a rear drum brake. The best set-up I've seen is to cable the brake into an indexed bar-end shifter. Then on a long descent the stoker can "shift" the brake to a tension that allows the captain to use less brake pressure to control speed. Besides, its traditionally the stoker's responsibility to wave and say "hi" to passing cyclists and pedestrians...