I added a phronesis entry to Designerly virtues.

Phronesis — Phronesis is tacit know-how acquired through hands-on experience. Being tacit, phronesis doesn’t always lend itself to explicit language, but rather, demonstrates itself in practice. When people who understand theory very clearly and who can explain it eloquently, struggle to apply that theory effectively and to adjust their methods to fit contingencies, phronesis is what is lacking. Another reason phronesis is important is “intuitive” design harnesses existing or easily-acquired phronesis to enable users to skillfully interact with a system without having to explicitly figure out or memorize how. Phronesis complements theory with tacit skills that enable mastery of theoretical and physical systems as well as effective improvisation where explicit methods are not available.