So, time and weather converged this afternoon and I decided to take a look at the driver's door latch mechanism. I took the plate on the edge of the door that covers from the back of the door handle, down to the latch mechanism and discovered that one of the rods looked to be bent in an odd way. I went and got a "persuader" (aka a hammer), tapped it on the bend a few times, and then opened and closed the door several times in succession. It seems to be working now. How long that caveman fix lasts remains to be seen, but the problem is solved, at least for the moment.