The idea for this puzzle came from a friend; unlike (it seems) many solvers, while being familiar with the illusion I’d not heard of Harbin.
The concept of moving blocks of cells obviously follows readily; but what sparked my interest was seeing the embedding of BERTHA in Robert Harbin, and the idea of “boxing” her. So the first task was to construct the wordplay clue / thematic hint, and to double-check its soundness: R/right “boxed” by (ROB/pinch IN/within), all around BERTHA, who I was glad to see was characterised in Chambers by the single word “bright”.
Once done, and noting that it could be lengthened or shortened as necessary by some variant on “imprisoning”, I set about the grid. The aim was to produce longer words initially crossing the vacant area after moving the central block (thus alarm / adenine and so forth) as well as forming at least one extraneous 4×4 box as well as the three required for the theme. Much trial and error ensued.
This done, I set about the clues, having at some point decided on the letter-position gimmick. I felt this was reasonably novel as well as allowing solvers to deduce answer-lengths once the skeleton of the hint, or some names, were revealed. I also decided on something that perhaps passed some solvers by – to hint at the theme by positioning the letters in blocks; 14 left, 14 right, 14 left. My approach was to first write a full set of clues simply with the hint letters correctly placed. Then I looked at what the alternative choices (at that stage arbitrary) happened to be, divided the clues into those where they could be readily replaced (eg by changing a terminal anagram indicator) and those that looked fixed by the clue structure. I then built the admittedly odd-looking set of girls’ names around the framework formed by the latter. Unsurprisingly some of my initial selection of ladies failed to make the cut – presumably they weren’t “bright” enough – but in the end I was able to assemble a suitably cooperative group. It might also be worth saying that Twisted Sister are (or more likely were) a “popular beat combo, m’lud”
My thanks of course go to my testers (on whom I originally inflicted a version without across / down delineators!) and of course Roger and Shane, who contrived with their usual skill to modify my occasional verbosity while retaining the substance of several clues. My own favourite, incidentally, was my spotting that the letters of ANOA could be derived from the “last pairs leaving” Noah’s Ark.
Feedback so far suggests that the puzzle appeared daunting (carte blanche, no symmetry, no lengths, vacant cells) but fell into place fairly readily once a foothold had been gained. I hope it gave solvers as much pleasure as I had constructing it.