All done, and artworks completed in the 3/8 (or8/3) fashion. Helped to PDM for the left hand column by my specialised education under the Ven. Sid Pask many, many years ago, so it popped out long before I'd needed to look for the supplementary 5 -letter thematic adjective, which I found by reverse engineering.
The bottom row followed fairly straightforwardly - but I still can't see where the 5 supplementary leyyers for that come from - the preamble is coy; is it another thematic adjective, anagrammed? I can't make the letters that must be added make anything.
Can someone give me a gentle hint, please?
I have to confess that I couldn't make pairs from the 14 thematic words - and instead of 4 & 3 - as the preamble - I had 8 of one fecund sort (thus the 8 artworks), plus 6 of the other variety.
Incomprehension on this detail for me; but fortunately it doesn't seem to matter in getting to a submissible solution.
And what's all this about a rhyme or saying that people keep referring to? I can think of a relevant simile that fits the theme, but can see no direct reference whatever to it in either the preamble, the revealed message, the grid - or the title, which I assume is a shorthand reference to what the thematic person did with their pivotal material to get their results. Or am I being obtuse?