Tnx for the pointer to the location of the last successful logfile. I look forward to the results of your thinking on how to somehow consolidate the world of LogFiles.
I just got off the phone with AppleCare -- they had me uncheck the OSX 10.4.5 Energy Saver option "Put the hard disk(s) to sleep when possible" -- these boxes had been checked on both of my computers.
Of course, the Mini had been doing its scheduled backup regularly, and the Pb hadn't; and now both of them are set "NOT to put their hard disk(s) to sleep." So I'm not entirely certain this is the fix for the PB.
The AppleCare rep put it well -- "so what you want is to be able to wake your Mac PowerBook up not from just sleep, but from deep sleep." Apparently the latter is when the disks are asleep as well. And the proposed fix is not to allow the disks to sleep -- which is fine by me, since all this is in "Settings for Power Adapter" anyhow.
More data on SD! performance by tomorrow. I promise to let enough time elapse before 0329 or 0330 to let any "deep sleep" set in; but I think that "deep sleep" is a thing of the past.