Originally Posted by MichaelW
If you want to replicate your solo position, you dont need a pro fitter.
True and yes, it is rather easy to transfer the dimensions from one bike to the next. In fact, a gentleman named Chris Rutkowski developed and patented the FitStik to make it an easy and exacting process.
http://www.cyclemetrics.com/.
However, the premise here is that there is not enough room to replicate your riding position - short of resting their head on your captain's backside -- and an alternative position needs to be developed to provide an efficient and comfortable ride. This is where the bike fitter's tools, experience, and the experimentation process on a Serotta Size-Cycle or your own bike / tandem mounted in a wind trainer can pay off.