[nick-garfield]

This is interesting.. I've never heard of the term "tacit knowledge" before, but it makes a lot of sense to me. It particularly reminds me of my experience being on-call at my last company.

Our systems were pretty unstable, and the most stressful part of the job was getting paged at 4am when everything was falling apart, customers couldn't use the app, multiple analysts would be sending messages asking "what's going on?", and as the on-call engineer, I happened to be the last line of defense (the system wasn't managed by a devops team).

In that moment, there's a lot of stuff that has to be done quickly: - orient yourself and figurate out what's going on (even in a sleep-deprived state) - prioritize mitigation over root-cause analysis - communicate early and often with the stakeholders present

This isn't stuff one can pickup by reading a "runbook". It took years of working with the systems, absorbing knowledge from my senior co-workers, and learning from past mistakes to get to a point where these priorities became in-grained in the way I approach outages.

So from my own experience, I would disagree with the definition that tacit knowledge is purely muscle memory or that it can't be improved. One's mindset can certainly evolve and I would consider that as "gaining" tacit knowledge.

I would even say something like music theory can be tacit knowledge. If you talk with musicians that do a lot of improvisation, they can certainly talk to you about music theory, but they're rarely "thinking" about music theory when they play. Just intellectually telling someone how notes/chords relate to one another doesn't transmit that "feeling" one needs to create great music.