My position on whether and how to "prepare" is gradually clarifying.  I felt a desperate need a couple of yours ago to figure out what to do, which meant I had to figure out what was going to happen.  It was very frustrating to realize how cloudy the crystal ball still is.  Most of the web sites and books devoted to preparation seem to have staked out a position based on little more than faith.  The contributing considerations for post-peak preparation include things like urban/rural, slow/fast, money/no money, cooperation/roving hordes, etc.  There is a legitimate case for each of these, and few rational reasons that I can see to prefer one over the other.

So the approach I have decided on is a combination of cost reduction, awareness, flexibility, and developing response options for various scenarios that can be progressively implemented as the situation clarifies.  This approach means that I have in a sense triaged my life.  I have decided that the most effort should go into being able to mitigate moderate scenarios.  I can not, at my age, move to a farm and develop within a couple of years the skills needed to survive a major social crash.  I can, however, plan to move to a farm if things get tight in my current urban situation, in time to develop grid-free heat and power and put in enough of a garden to make life easier - assuming the survival of some infrastructure and cooperation.

I will not plan for a major crash because I believe the cost/benefit ratio of doing that is too low, the opportunity cost is too high, and the cost of a false positive (preparing for a major crash that doesn't come) exceeds what I am willing to pay.  Also, I am under no illusions about the probability of my long-term survival in such a situation.

I will keep my finger on the pulse of developments, and mentally and financially prepare myself for the possibility of making fairly large changes in my life if they become necessary.  The kind of decline I am interested in preparing for will give at least six months warning, and will be gentle enough to allow me to reorganize during the first six months it's happening.  Anything worse than that is too problematic for rational preparation.