I can see that happening. If only one person on the team loses interest or is injured, no more team. If a tandem takes a relationship where it's going, only faster, then perhaps someone's partnership got to the finish line before delivery.

I'm reminded of a story the builder of my first tandem told me. He had a couple who were having him build them a tandem. He wasn't cheap; his motto was "Why Pay Less?" He wondered why the husband was insistent that the stoker compartment be made bigger than was appropriate for the wife. He got his answer a few months after he delivered the tandem. The couple was getting a divorce and the husband already had a new stoker who just happened to fit the bike perfectly.