Something I forgot to mention here that supports my view that designers of modern cars are not thinking about this problem at all: after battery power is lost c

Something I forgot to mention here that supports my view that designers of modern cars are not thinking about this problem at all: after battery power is lost cars lose their maps and tables for ignition timing and fuel delivery. After a usually short period of time (20 minutes is typical) that data is lost and the engine etc. has to 'relearn' when the power is restored and the vehicle is operated for a time.