"a dirty secret of regulation is that it frequently influences conduct most effectively when it is capricious and opaque. Any regulatory system will reveal its vulnerabilities over long use. If it addresses economic problems in a predictable way, savvy investors will find a way to "game" that predictability. You can draw an analogy with antidepressant drugs. There is no permanent right match of medication for a depressive. Antidepressants work only until the mind (or is it the brain?) finds a way around them, at which point a new, unfamiliar drug must be substituted. In the same way, no matter how good the content of a regulatory regime, it must change periodically if big market players are to be kept from profiting off it."
http://www.weeklystandard.com/Utili