All done by Saturday night, with no help, for a change. Some almost impenetrable clues, but enough quite ridiculously simple ones to get a rapid toe-hold, and then the straightforward entering of answers led to rapid progress.
I'm still relentlessly dogged by Serendipity - although not quite so laser-targetted in time as last week - see my post #188 in the 4717 thread; this week's theme refers to participation that I've been promoting - in modern terms - in the same, but rather wider-scoped field as the historic 'participants' - since the early 1980s - and I was aware of the 'memorable action' - but not familiar, to my shame, with the remarkable owner of the thematic name.
It's prompted me to write an article.
Don't we Listeners live and learn!
(But
stilll don't see how the across and down clues 'link'.
- but does it matter?)