Sometimes we need some complicated view to be displayed (such as generating complicated table). Most people suggest that in MVC the View must be as simple as possible (don't have too much loops, etc). So what we have to do is to hide away the complex code by putting it at somewhere else. The following are few places options to keep the function:
I assume you are familiar with accessControl standard filter. It allows you to separate privileges to run some action from action code itself. There is however one problem with most common usage - you cannot use bizRules, at least based on some parameters passed to 'checkAccess' just because it is hard to pass them in accessRules() result.