Well, not entirely useless, but not accomplishing what it was intended to.
First I had some errands near home. Those went reasonably OK. Then I was to drive up to the City for an SF Symphony concert. Traffic was very heavy and slow, and it took twice as long as usual. But I was early enough that I still had time for dinner in a Chinese restaurant on the fringes that I've been meaning to try for a long time now. (It was quite good, though the dish I had turned out to be one I've had under another name at another place recently, where it was even better. Though this time I did have the pleasure of watching the server, who I think was also the chef [very small restaurant], wave my dish under the noses at another table on its way out and say, "You should have ordered this one.")
That was my mistake, for if I'd bowed to the traffic gods and parked at the end of the BART line, as I sometimes do, I wouldn't have encountered the problem I found when I arrived, which was: No parking. At all. Even the pay lot I sometimes use for last resort was full, which I'd never seen before of an evening. One reason was some kind of motorcycle demolition derby being set up in the civic center plaza, but there must have been more. On a Thursday?
It was still an hour before showtime, but, given traffic, that wasn't long enough to drive back out and take BART in. I wasn't particularly interested in the program; it was just something that happened to be on my series. I had a choice of either continuing to search for an unlikely or far-off parking space, or just giving up and going back home. The latter sounded like the less unpleasant option.
So I drove home and cleaned the oven.