Well, everything is finally fixed. While the road to get there was a bit on the bumpy side, and the repairs took longer to happen than they should have, in the end things got fixed.
As expected, there was a load of confusion over what was actually wrong. I got a call from the technician in the morning (even though I specifically said that the problem was starting late in the afternoon). He didn't leave a message, but I called back on the number on the Caller-ID, and I mentioned what happened. He looked at the schedule and noticed that there were several service calls on my street. The light bulb went on.
After a call in the afternoon saying the problem was fixed, and finding it wasn't when I got home, and calling back to say it wasn't fixed, and getting a recording that there was a problem in the area, requesting a call back when the problem was fixed, and later getting the automated call that it was fixed and it wasn't fixed, calling back and getting a recording again that there was a problem in the area........
The cable service went dead a short time later. I mean dead as a doornail. No Internet. Not any sign of a signal. This happened for a half hour. At that point, I knew they were working on the trouble. It had the signature of what happens when they are in the process of replacing a part that's broken. About a half-hour later, service returned. The TV signal was good (real good) - the TiVo reported no signal errors at all (RS Corrected/Uncorrected). No digital distortion.
Things are looking good at this point. The signal strength is a bit low in my opinion on some channels (lower than it was), but it is a good signal. I waited until now to update everyone, because I was half-expecting that I would get home from work today and have to call once again, but it was all working as well as last night. I'll even say that the number of errors being reported in the signal are less now than before this whole problem started.
So while I do feel that the journey was a bit long and frustrating, in the end the problem was repaired.
This is what I've always said about Time Warner Cable. They are a company that is too large. With that size they've become so fragmented that while they independently have a lot of talented people, it is hard to get those people to the right place. This isn't specific to Time Warner either - it explains the way a lot of large organizations work (organization being an oxymoron in this case). Growth is good. Unbounded growth, like in people, makes the organization fat and sluggish, and unable to get anything done. Figuring out what the boundaries are, and who defines them, is at the heart of discussion in various disciplines (including politics).
Anyway, I'll never know who figured out what the trouble was in the cable transmission system, and what they did to fix it, but to those people who worked in 90+ degree weather last night, thanks. I appreciate your efforts.