ChrisT, you always amaze me with your depth of knowledge
I believe Escorts are the real unsung heros of our car culture. The Hondas and the Toyotas get all the press, but we get just as good of mpg, with lower costs to buy a good used one and cheaper parts. When I go to the junk yard the Hondas and Toyotas are picked clean, the Escorts are ripe with sweet parts. Why buy a Civic for 3K when you can get an escort for the same options in an Escort for 1.5K and have lower miles and get cheaper parts. Just my two cents....My grandfather bought a model T when they first came out and my family has bought Ford ever since...it's in my blood....
Zach, I don't focus too much on TPS when I drive, because I am constanly Pulsing and Coasting. My TPS when pulsing is up to 36. I'd say our 55mph tps is within a reasonable percentage of each other, I wouldn't say mine is so much better than yours. One year ago you were turning in 42mpg tanks without the Pulse and Coast, so your car is cabable, you just don't have the oppertunities to repeat those successes. Just advance what you can right now, don't focus on the big numbers (as if it were winter) and make some progress with what you can.
You got me interested in the SeaFoam, I'm gonna try it also. Replace that tensioner, if you know it to be the probelm, before it causes some real issues. While it's off, spin the other idlers to see if any of them have rough bearings that may be on the way out.