Wow, these are really great insights!
A few of things I see I didn't mention in my original post. First, we were thinking of riding in the dryer time, I should have made that distinction, we are retiring at the end of the year but not touring till summer. I was thinking is late July through early September. Second,If we do the compete route we were thinking self-contained using a trailer as a way of reducing the stress on the back wheel. A probably staying in hotels, Inns and B&Bs. Last, we've done short tours of a couple days so this will be our first serious tour.
I've been talking about this for years and one cool thing that has me thinking of a shorter ride is our (at tour time) 17 and 19 year old grandsons would like to go with us with them taking turns riding with us and driving our van. This would lighten our load considerably with only carrying what we need for the day but they wouldn't be able to ride more then 2 weeks.
Doing a Google maps check it looks like SF to SD is just a little over 600 miles which would be a good distance. Earlier this year two ladies from the UK were doing an around-the-world ride on a tandem and came onto North America at San Fransisco and rode to San Diego. their comments were that the California coast was the most beautiful they had ever seen, I can't imagine what the coast north of there must be for you all saying it is the prettiest of the coast. :-) Maybe we could ride the top section of about 800 miles the next year.
This has been awesome and I look forward to other thoughts. Our tandem is a Bushnell 9 speed XT rear and Ultegra front with an 11-34 freewheel. The Wheels are White Industry hubs 36 front and 40 rear laced to Velocity Dyad rims. Braking is "V" rim brakes and Arai drum Brake.