Andy,
I'm so sorry to hear of your wife's recent illness. A heart attack is a terribly serious thing for the person involved and for loved ones, and has such a great effect of lifestyle and activity during the healing phase and well beyond. I know some of our members are dealing with similar issues themselves, and are far more able to relate with firsthand experience than I.
Please pass on our best wishes and remember the Forum is a great resource as she continues in the next phase of her recovery -- exercise. Perhaps doing so on a bicycle (and a tandem Thorn, at that!) will make it a bit easier. Having you at the helm can only help, and it is so encouraging she is able to ride.
Andy, as you ponder what to do with the RST, I'm sure you'll receive many offers and suggestions, and if you decide to sell, remember our Private Classified > Bikes For Sale category. I'm certain you'll find a ready buyer soonest.
Best wishes to you both; nice to have you back aboard.
Dan.