Dave, I admittedly wasn’t considering the relative perceptions of value of skills. And sure, sequence the skills however makes sense (presumably, looking up codes is not only lower value, but lower learning; even I have been able to do it on flights and trains with web interfaces ;). Which doesn’t, to me, mean put the codes in the head regardless.

That explains the popularity of Jeopardy, but this bias is also part of individual or organizational resistance toward “putting information in the head last.” When someone’s well versed in a field (or when he thinks he is), he doesn’t readily see the difference between task A and task B. My example at Amtrak was checking train schedules: you can check train schedules without knowing the three-letter city codes if I give you the codes — and checking train schedules is a richer-looking task to the newcomer than looking up a city code is.

What that means in practice is that if you’re learning to be a reservation agent or a ticket clerk, I can on the one hand just supply the codes (so you can practice various schedule scenarios), and I can show you how to look up codes (so you know how to find them when you need to). My own opinion is that requiring you as a novice to look up codes every single time gets in the way of your learning the higher-value skill.