Jim, Sorry to hear about your wife's difficulties and glad to hear optimism. I was way to obscure in a failed attempt at humor trying to note a lack of hills on our respective canoe trips, water being pretty flat. My wife and I enjoy biking rail trails away from traffic and hills. We contemplate a tandem from time to time but haven't borrowed or bought one yet.
Zipp, Orange sounds like a nice destination and, as I recall, in a hilly area. I bet you like it.
I discovered 30c Grand Bios tires won't fit on my Raleigh Cadent 1.0. I'm contemplating using it (triple front chain ring) for the Great River Ride. Unlike the flood plains of the Concord, Sudbury and Charles, there are rumors of 8000 ft of climbing.