Update: Speaking of unplugged...when Herself returned home, I told her of the events and that I would get another valve, etc. When I got home the next day, I noticed that the drip had stopped. When I mentioned this to her, she allowed as how she had unplugged and plugged the washer.(no mean feat as they are up on pedestals and the back edges are under wall cabinets). When asked how she arrived at that, she said that whenever her fax at the office (a big Savin color printer/copier/fax server) acted up, she had to do the same and reboot it.
Sheesh. Go figure.