I'm not sure anyone's answered the question about the puzzle's title yet. The "originators" have another title that begins "Tell me what..." Applying that instruction to the finished grid is useful, I think. Open to other interpretations.
I was there, too, Hounds. When the final PDM hits it is like stepping on a rake. “Refrain” is doing a lot of work and some of the suggestions about using a blank grid to trace the bars might help you get that blow between the eyes.
My version of reducing the number of bars to the thematic 66 results in a final grid with lots of non-words. There is no mention of this in the preamble, but I am sure I have the right solution. Do other solvers have non-words in the final grid?
0pt0, I think that this is a variation on "bars and numbers need not be shown". The solution is so clearly (and cleverly) right that I'm not fussed about the "word" impact of removing bars.