I think at the end of the day, what you need is to have at least one person on the team who is confident enough in her ability to understand what the code does that she's willing to rewrite that code into a simpler form. And you need to be able to recognize that skillset and allow her to do that.

The problem is that a lot of developers _think_ they can do this, but few actually _can_ do this. So you can't just let anyone who steps forward offering to refactor the code do it, or you can wind up with an even worse problem--code that's still really bad, but doesn't even perform the original function. This means you waste time going in the wrong direction while the person who potentially could turn the ship proves her skill to the powers that be. It's a real conundrum, and the only way around it is to do what you can to ensure that your developers actually understand what they and others are writing and that they're not just throwing spaghetti at the wall until finally the pattern of sauce looks like the rose wallpaper that was specified.