I can tell you why I did abort my T/A tour this year.
I borrowed a Hase trike tandem with trailer and the gears were just to high and I was slower than I needed to be. After knee pain during the first week and the realization that my speed would never allow me to finish I decided to slow down (with my son) and enjoy what we could. We made 600 miles across Florida and had one of the best times of my life, and definitaly one of his.
The experience with my son was way more important than my initial goal of the transam. We made a huge memory for us and I can just imagine the stress of trying to make impossible miles each day would have changed the positive memories to something less.
Now I am planning a more modest week tour next summer, I learned something from this one.
Steven