It seems like the article may have confused two concepts from information theory. He talks about entropy (without explicitly naming it) which can be used to bound the best possible data compression scheme.<p>Data compression is not the problem with interacting with devices though. What he should be instead looking at is channel capacity, where the user is encoding information for transmission that the device will receive and decode.<p>Maybe that's too technical for the nature of this article, but oh well.
It isn't really sensible to distinguish between "meaning" and "information." As he notes in the side bar, measurements of "information" content depend on the statistical model used. "Meaning" is just information content in a statistical model we don't currently know how to formalize: patterns of human thought.
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?<p>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).<p>I generally feel design needs a bit of the information think as well as a specification of a concurrently evolving "user state".
Shouldn't the efficiency of an atomic-synchronized watch be infinite, since there is no user input? Having a crown which neither needs to be pulled out or pushed in would give 100% efficiency, and the no-input watch seems strictly better than this.
I thought this was a pretty interesting article but I don't really buy the analog vs digital watch comparison. Mostly I don't agree that turning the crown is only 9.5 bits. There are 720 possible combinations and you have to move through on average 180 of them to get to the right time (assuming you can move forwards and backwards). Each tick of the crown is a movement, just as each button press is. In that case the analog watch drops to just over 5% efficiency.
I guess the best way to set a watch would be using some type of binary search then.<p>edit: quick mockup of what I mean: <a href="http://sberan.xen.prgmr.com/watch.html" rel="nofollow">http://sberan.xen.prgmr.com/watch.html</a>