Philipp Lenssen lists common misuses and abuses of CSS such as layout-based class-names (e.g. “bigredtitle”), and "unspecified, undocumented, and forgotten class-names." I can relate to that, as I created my CSS files based on code stolen from half a dozen sites and I didn’t really clean them up and consolidated the styles I use (next time, I guess, if you know what I mean?). Here is the only mention of "CSS refactoring" I’ve found while "CSS cleaning" didn’t retrieve anything.
This is a natural evolution for CSS editors such as TopStyle (which, to be fair, already does site reports to ease management). Much like Dreamweaver cleans up HTML spaghetti code (e.g. nested tags), web design tools will need to do garbage collection to ease our lives. Of course it doesn’t hurt to minimize the pollution we generate in the first place by writing clean code, but big sites created distributed teams (with shifting staff) and faced with the burden of time will create the need for these tools no matter how tidy designers try to be.
06/24/04 update: What’s in a name (CSS naming conventions), CSS Editors.
01/20/05 update: Refactoring Web User Interface, Writing Lean CSS, Redundancy vs. Dependency.
02/18/05 update: Discussing CSS Management and Optimization, Applied CSS Management and Optimization, Integrated Web Design: Strategies for Long-Term CSS Hack Management.
03/15/05 update: CSS Tips & Tricks.
08/26/05 update: Architecting CSS.
07/08/07: Frameworks for Designers.