That looks like an awesome tandem. Love the paint job.
Looks similar to Calfee in construction with some differences, notably the rear triangle.
If I didn't already have a Calfee I would be talking to John.
Didn't even know John was building carbon tandem frames.
You probably know this already but John built the bike that Andy Hampsten won the Giro on back in 1988:
Belgium Knee Warmers?: Andy Hampsten's Land Shark