Decouplers - and ease

Ok Steve, we will have to agree to disagree!

I just happen to think that looking at a component and the drawing
that produced it are two infinitely different things. Reverse
engineering those fine dimensions, teeth profiles (non-standard),
radii, and tolerances would be hard work (VERY), but knowing what the
staged heat treatments are something else. This is effectively a
crash-box dog-clutch, sounds OK and the production technology's
understood, but it still has to work reliably under very high shock
loads with potentially little oil around it.

Anything's possible, but many things are not easy - that's assuming
this knowledgeable person with a fortnight of Sundays and more to
spare has a pretty amazing machine shop at their disposal as well as
all the case hardening and heat treatment stuff...

I'm just so glad someone out there is set up to make them - and can
see why they charge a lot - a small run of complex components, just
the selector fork has about a dozen different radii marked up.

Maybe we can agree that you overstated the 'ease' and I've overstated
the difficulty?