Although I chose to cut the ride short, I would by no means class it as a failure.  It was intended to expose flaws and weaknesses in the hubris that is woven into my cross-country plan and give me time to decide what to do about them.  That it has done, in clear and definite fashion.

First: being under-trained is a serious liability.  Some people "just set off and ride themselves into shape" in the first weeks of a long tour.  I simply cannot take that approach.  The fact that I've been less diligent than I ought to have been in the past two months has been brought into clear, sharp, unmistakable relief.  There's not much time remaining now to rectify that but we'll see what can be accomplished, and gauge whether it's "enough".

Second: ounces, pounds, and liters of gear count.  Some of what I'd been planning to take with me will have to go (or, rather, NOT go...).  The Tyvek tarp I made, for example, which seemed like such a good idea, added a pound or two of weight and some volume I don't really need to carry.

Similarly, the Kitchen Sink will stay home; when camping I'll mostly be in places that have showers and possibly dishwashing sinks, so there are opportunities for laundry and dishwashing that do not require me to carry one of my own.  

The liter size backup / spare capacity water jar is going to stay home; it's just too awkward and consumes pannier volume I could use for more important things.  I can tuck the water filter into smaller spaces rather than using the jar as a container.

I stocked up on "provisions" before leaving home, only to return with much of what I had bought and carried with me.  So, I could do better in that regard.

I'll still cling to the three changes of bike clothing concept, but may delete one of the off the bike tee shirts even though they're very light and pack small.

Two LED camping lanterns, no matter how lightweight, are one lantern too many.  One of them will stay home.

Some of the kitchen gear, namely the extra microfiber towels I tucked away, is not needed.  Paper towels will do in a pinch, and are readily available from a variety of sources.

I think my tablet computer will stay home; you'll just have to suffer the inevitable typos that proliferate when I'm composing text on a phone.  I'll fix them later, in a series of final editing sessions.

A smaller, lighter tent could shave three or more pounds off my load.  I'm loath to take the plunge, as it would add a fourth tent to my shelves, but I could give at least one of the others away in compensation.

Perhaps it's time to reflect on my choice of sleeping gear.  I like my now 15-plus year old mummy bag well enough but there are smaller, lighter options that seem to be adequate.  And do I really need to take the 3/4" thick Therm-A-Rest, or would my 1/2" model be adequate?  It's marginally smaller and lighter and, as I've noted in the beginning, ounces add up quickly.

If I can contrive to cut eight to ten pounds off the gear, it'd go a long way toward making the long trip potentially viable.  There are, of course, still all those other factors (heat, weather, blah blah blah) but this is an area where I have greater control and therefore more opportunity to make changes.