Thanks to my trusty mehcanic Bob at Kars, Inc. of Westerly, RI, the idle/stalling problem on my 94 Escort is history!
Turned out to be a blown intake manifold gasket to the head at the No. 1 cylinder. Idle is smooth as silk at the usual 750 RPM now. Fuel filter was replaced as well, as it was way overdue.
Bob's diagnostic that found the leaking gasket was the good old squirt around the intake manifold with carb cleaner as someone here on the list had previously suggested. Idle smoothed right out when he zapped the No. 1 cylinder joint. There was a big chunk of gasket flapping around there. I did not see nor hear anything unusual there in all the time I was dealing with it myself. I had not done the carb cleaner squirt diagnsotci myself though.
Lesson learned - when the going gets tough, call in the expert! At least I was able to tell him what potential problems it wasn't, based on my troubleshooting.