What should really blow your mind is the precision of the original metalworking and gearing, well before the age of clockmaking and watchmaking.
An item like that to spring in to existence without any record of a history leading up to it or a history of devices descending from it really makes you wonder whose imagination it sprang from and why it wasn't recognized that these principles had further application, or, alternatively could point to lots of stuff (including knowledge) getting lost.
An explanation for that fact that so few devices remain that a record of history seems to be missing, could be that they were made of metals (copper, bronze, etc) which were quite precious in that time, so the devices probably got recycled. Image that, some warrior smelting a few antikythera machines to forge a sword!
Sure, but there is a bit of a difference in precision between a man sized gear or one that would not be out of place in a modern gear driven clock.
I think you got confused by the wording of "precision of the original metalworking and gearing", original as in 'not the lego version', not suggesting it was the first use of gears.
In a clock precision in the metalwork in the gears is important to cut down on friction, etc. But I'm not sure if the saem can be said for this ancient computer.
Someone correct me if I'm wrong, but it seems like what is important here is simply the ratios of the number of teeth on the different gears.
I mean obviously all the parts have to mesh when the device is cranked but it doesn't have to turn terribly smoothly to work.
I disagree. Devices like Antikythera would have probably cost a lot more than their weight at their time. One of the reasons that artifacts don't last is that some metals like iron don't last because of oxidation. Bronze however resists corrosion, and especially sea corrosion really well. And Antikythera is one of those bronze devices that we got out of the sea, it lasted two thousand years underwater.
An item like that to spring in to existence without any record of a history leading up to it or a history of devices descending from it really makes you wonder whose imagination it sprang from and why it wasn't recognized that these principles had further application, or, alternatively could point to lots of stuff (including knowledge) getting lost.