Update to the story. I talked with a coworker who is an auto mechanic with our company. He thinks it is a solenoid / electrical issue, rather than a mechanical one, and he has worked on several Honda automatics. There is a shift solenoid valve on the exterior of the transmission, and it has two fine screens where it mates to the transmission hydraulics. I haven't taken it off yet to inspect, but there is also a way to test the solenoids. I think that this may be the culprit, because depending on which solenoid is activated, if at all, depends on what gear the transmission is in, like a shuttle valve on hydraulic systems. I think what is happening, is that the transmission is getting stuck in 4th, because of either fluid blockage (screens clogged), or solenoid failure.
I cranked the car this past weekend, and when I put it in Drive, it pulled forward. So, I drove it down the driveway and onto the street. The 1-2 shift was fine, but 2-3 had a little slip, and 3-4 was okay. But as I slowed down, it never downshifted, so when I had to stop (because someone pulled in front of me), it wouldn't pull any more. Fortunately, I weas only about 1/4 mile from home, so I called the wife and she brought my Jeep so I could pull it home. I'll try to get to that valve assembly as soon as I can. A new one is less than $200, but I may go to Pullapart to see if a used one is available and can be used instead.