How does this approach relate to the value of "don't make me think" in design? How "good" is, for example, a digital watch that asks you to enter the time you want to set expressed in base-4 by selecting one button from a set of 4 at a time? According to Raskin's measure, such a design would be much more "efficient" (and bloody cool geeky surely) .. but is it "good" design?

a) the effect of seeing the result of each of your actions immediately is not being accounted for by this model of "design efficiency" and b) how such a "feedback" relates to the "current state of your mind" instant by instant isn't as well (thats the subjective bit).

I generally feel design needs a bit of the information think as well as a specification of a concurrently evolving "user state".