Update time:
Took the car to the detailer today after school (around 1). I drove up, got out, and went inside, where I talked to this lady. She was sitting next to one of the mechanics, but apparently she was supposed to be the one to talk. So, I said, "Hi, I need to have my PCM updated or reprogramed or something..." And she said, "Oh, ok. We should probably run a diagnostic, though." I contemplated spending double to get a diagnostic AND have my PCM relashed, and rejected the idea, and said I would like to just get the PCM reprogrammed.
At this point, the mechanic chymed in. He asked me to explain the problem, which I did. He asked all the same questions, had all the same responses, and I had a counter for each one. "It's summer, so the AC is kicking in more." I responded "Yes, but even without the AC, I still get horrible performance and bad gas mileage." He suggested a CEL, which I didn't have, and I countered that I've replaced the TPS, CTS, and CPS, along with cleaning the MAF. I also told him my secondaries were still working, despite the old age. He theorized the plugs were bad; I told him that although I replaced the motorcraft with Autolites, the problem didn't go away. He said the fuel filter was maybe bad; I said I had replaced it twice.
I then told him if he could search for a TSB on the subject; he got my VIN, but couldn't find a TBS relating to the PCM. He also said he would prefer to run a diagnostic instead of flashing the PCM (I guess reprogramming the PCM can be bad? Maybe destroy the PCM?) Anyway, he took the car in and ran a diagnostic, and told me "Hey, everythings fine. The tranny seems ok, the fuel system is optimal, all the pistons are firing, the oxygen sensors are cycling correctly (this was a concern of mine), BUT, I did find that the PCM needed to be updated. So, right now, I'm recalibrating it. This update addresses 9 different issues that have come up over the years. I'll only add 25 bucks to the diagnostic cost (as opposed to the 90 it would have been alone.)
So, he recalibrated everything, and 125bucks later (argh), I drove away. The drive home was uneventful, although the car had tons of power when I needed it (not much stop and go driving). The test will really be this weekend, when I drive down to Galveston, to see what my gasmileage is like.