With 15 years and several thousand posts, with thousands of links between them in the archives, page rendering is now so slow (without cacheing*) that I am going to have to retire the site and start a fresh one.
That still leaves me with the housekeeping problem of how I keep links to important older posts working (without cacheing*).
(*) Seems I am to remain without cacheing, thanks to the permalink option I selected way back when I first migrated to WordPress, where every link is a query – which would be flattened by the cacheing, thereby losing ALL existing archive links. Need to find some link search and replace mechanism that doesn’t screw up the database, or progressively manually migrate the important links. The strategy adopted will affect whether I can preserve the main address for the site.
[Post Note : looks like with a change of theme, switching permalinks does maintain backward link compatibility in both the cached and live pages, so with a couple of other tweaks I can fix this. Tried out a few ideas on another blog, and will update here in a week or two.]