Brian,
Well, lets see? How about a tandem with curved stoker seat post (Jack Taylor style), Hellenic style seat stays, Hetchins curly chain stays, triplane fork crown, extended head tube, and special cut out modified extended tange investment cast lugs. We'd better paint it in a metallic pearlized smoke effect three color fade with stripes around the lugs. Make sure we've got braze ons for six water bottles, fenders, touring racks, and generator dynamos!
Oh, by the way the tandem Captain will be 6' 6," and concerned about toe clip overlap, his wife who rides as stoker is 5' 0", most of which is torso. On second thought, let's reverse their positions to really confound the geometry! A noted east coast titanium framebuilder has suggested that we use a 650 front wheel and 700c rear wheel, as well.
Is this closer to what you had in mind?
Regards,
Carlo Carr (Think I'll send this request to Seven Cycles for an estimate)