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I appreciate the compliments, Scorpius and Nick, but please remember I am one of the weaker solvers in this pleasant forum and it's extremely rare that I can finish a puzzle of this difficulty before anyone else, if indeed I finish it at all. I didn't get off the starting blocks with Wiggles by Sabre last year.
I do find it interesting how different puzzles attract such varied reactions. Some puzzles which I have found a tedious slog have met with great approbation from others, and vice versa. I didn't enjoy the recent Sabre - a grid fill on the level of an easy Mephisto followed by a long grid search for words that might be coded doesn't float my boat at all - but others plainly enjoyed it. That's all to the good, and vive la différence.
For me, there was always light at the end of the tunnel with this one (even if sometimes it was a train coming at high speed) and although filling the grid was slow, it never degenerated into what I call sticky label peeling syndrome. The left-right symmetry was an enormous help, without that I suspect that it would have been impossible.