I remembered an illuminating post by the magisterial CarolHaynes on how to cancel subscriptions from companies that make cancellation excessively difficult. I didn't seem to have a local copy, so I went looking for it using DC's search feature. I couldn't find it, despite a fairly determined attempt. CarolHaynes remembers the message herself but also couldn't find it, and points out that she thinks SMF has been occasionally losing messages. Obviously searching wouldn't turn up a message that was no longer in existence.
So... has anyone else seen this problem? The search facility may not be very good, but it should have turned up something. Has anyone else found that posts they know they made have quietly disappeared?