I think with hypnosis using visual fascination, you generally want to have not just a visually compelling object, but a complex vocabulary to describe that object. But, I think more than just compelling language, ideally you want interesting thematic ideas, too. Which is part of why I think pocketwatches make such good objects of fixation.
Like, part of it is that clocks are just such interesting objects, historically. Their development and the importance placed on them is the history of sailing and a history of colonialism. A proxy for the desire to conquer the natural world. The idea of empiricism and christian science triumphing over nature (and, further, everyone not christian). The creation of better and better clocks, both models of the world and models of the heavens, reflects these ideas just as much as it enables their impact on the world. Even their more recent secularized incarnations can't quite throw off this weight. A "science" from the start designed for conquest.
The idea of enrapturing someone with clockwork, then gains all this added weight and depth. Clockwork is often understood as proxy for this conquering science. You're trapped within it, or converted into it, and seen as something rendered into a construct. Made robotic, simplified, dehumanized, objectified. The idea appeals on multiple levels, doesn't it?
In general, I think that agreeing with the premise of an all consuming science that subsumes everything into its perfect clockwork universe has a lot of sauce to it. Like, it's a horror type kink, I think. Imagining yourself as something with no substance to it. Proved to be without anything that cannot be understood and reduced to the motion of gears. That everything you are can be subsumed under something else. It's a pretty popular idea, determinism opposing free will. I've shared my thoughts on it before. I like it in part because there's no real point arguing against it, it's functionally true.
The intrigue of clockwork imagery focuses this further. By describing the gears to you, I cast myself as someone who understands them and is familiar with them, while you fall into them. There's a sense of a mystery there that I understand and you don't. As you're further affected by it, as you're drawn into it, you're pulled into something understood as my domain. Out of your depth, you have only my words to guide you. I think much of the hypnotic space likes to play with this kind of thing.
Here, this set of ideas is (as intended) perfectly compatible with a controller, with one standing above and manipulating all the strings. Casting the hypnotist as such fits perfectly. This role of someone who understands everything, and through this understanding can do anything. The idea of a clock as a perfectly controlled space, nature rendered into tool and weapon. Clockwork as the workings of this, gears, spring, and plates as the dimensions of your world.
We get a set of cues, ticking and tocking, gears unwinding slowly around you, a tour de force of design ingenuity. Drawn in so completely to the idea of being understood perfectly. The promise of it, of being conquered by this toxic idea. Just in line with the inevitability of it, time only goes in one direction. Modern clocks are functionally perfect, there's not really anywhere to improve on the core design anymore. But, we still make them prettier and prettier to look at. Don't you want to be pretty to look at? The clock becomes proxy for you, too, in the scene. I think it all comes together very cleanly. Like clockwork, I guess.
