I did it!  Finally, despite best efforts to prevent it, I have slipped down into the dark side.  I now officially have over 100 Firefox tabs open.  Thank goodness that memory-sieve SessionSaver has been uninstalled and TabMixPlus has taken its place as my tab manager of choice.  Now the whole thing is only moderately untenable, though it still dumps buckets of memory out.  Currently sitting at 417MB or RAM taken up by FF.