Self-enforcing speed limits, and control through deterioration

Architecture & urbanism, Blog, Design with Intent, Motoring, User Psychology

Interesting discussion at the SABRE roads forum on self-enforcing speed limits in the UK–current regulations mean that if a 20 mph zone can be created through a ‘self-enforcing’ architecture of control (i.e. traffic calming) then it doesn’t legally need any signs to remind drivers, other than at the entrance to the zone.
The point’s also made by a poster that allowing a road surface to deteriorate progressively to the extent that drivers have to slow down (or find an alternative route) is a cheaper way to effect the desired intention: is this ‘gradual deterioration of experience leading to change in user behaviour’ ever used strategically as a technique in other fields?
An analogue (no pun intended) might be the way that, increasingly, the BBC (a TV company with the luxury of intimidation-enforced public funding), is putting its more ‘highbrow’ content on the digital channel BBC4 (heavily advertised in other BBC media)–the deterioration and reduction of, for example, intelligent cultural (and, especially, science) programming on the ‘legacy’ analogue channels BBC1 & 2 is very clear over the past few years, leading to a gradually increasing frustration and desire for a solution in the mind of the viewer without digital TV, even if only subconscious (though it’s become fairly conscious in my own mind!).
The viewer now perceives dissatisfaction with the current state of affairs, and will apparently ‘voluntarily’ switch to digital TV (which is of course, the government’s aim, since the analogue spectrum will make a nice windfall at auction).
You might call this idea a ‘water torture’ architecture of control–it’s not rigid like product architecture, but it has the desired effect of changing consumers’ behaviour. More examples, please.