I first read this in 2006, but have been thinking about it again recently. I share this experience.

From his wife’s perspective, Phil said, it looks like he knows how to do everything. But his own, subjective experience is very different. He doesn’t really have detailed procedural knowledge of most tasks. He’s just very good at discovering that knowledge.

“What I’m actually doing is figuring things out on the fly,” Phil said. That’s what all IT adepts do, all the time. We do it in such a rapid, fluid, and automatic way that we don’t seem to be constantly learning or relearning. But we are, and Phil’s insight prompted me to recalibrate my thinking on this matter.

The clash of these cognitive styles — knowing how to do things versus knowing how to find out how to do things — is a source of friction between IT folk and our clientele. From our perspective, it’s annoying to be asked constantly to write down detailed step-by-step procedures. If we don’t rely on them, why should anyone else need to?

— Jon Udell, The tacit dimension of tech support

See also: Personal Knowledge by Michael Polanyi. My quotes don’t include it, but Udell references Polanyi’s “tacit knowledge” concept.