Dave – your observation that “isn’t any good design somewhat coercive?” seems obvious to you, but you’d be amazed how much debate that issue can stir up. I think many people would argue with the ‘coercion’ definition, preferring to see it as the user ‘agreeing’ to be ‘tunnelled’ (BJ Fogg’s term) through the infinity of possible choices towards the ‘most useful’ ones, or ‘nudged’ towards adopting a certain mental model (Thaler and Sunstein – whose work I’m going to be discussing on the blog ASAP).

But I know exactly what you mean when you use the term ‘coercion’ and I think I’d argue – like the Johan Redström article linked above, or to some extent Richard Buchanan, that everything that is designed, is designed with the intent that certain user behaviour results. Whether you call that coercion, persuasion, intent, prescription, inscription, user-steering, whatever, the idea is much the same.

If you want to work your iPod, you have to adopt a certain view of the way your music is organized. If you’ve organized your own library with iTunes, you have been coerced into adopting a certain mental model of your music library. It’s the price of entry.

The iPod has solved the challenge of organizing a large music library for fast browsing by category extremely well, but it’s done so by limiting the way you can look at your library, and maybe eliminating some valuable paradigms (browse on my iPod by track length comes to mind…maybe handy for someone providing “walk-in” music for a business meeting where the presentation will begin in 15 minutes).

The same could be said for any UI. You want to play a particular computer game, it means you buy into their method of manipulating their world, because there is no other. “accept to play” is what’s happening, though I doubt any player realizes it’s going on – it’s a given.

This is something I’ve been learning about recently in regards to web site design and development, and there are a number of research techniques / analysis tools we’ve learned about in that context that might be useful in physical-world design. My firm’s been trying out Mental Models (as described by Indi Young: http://www.rosenfeldmedia.com/books/mental-models/), for example, a tool I can easily see being used to design web sites, physical-world goods, and even business processes while keeping the end user in mind.