On: Simple rule of thumb for measuring the perceived complexity of a user interface

Sounds like therbligs are back. After 90 years, and without the ridiculous name.

http://en.wikipedia.org/wiki/Therblig

Sure you could view the UI as a set of "motions", but the argument of this article is about how you could simplify such analysis: just count the number of concepts or elements presented to the user. The smaller the count, the easier the UI would feel.