I'm all for styles. When I'm engaged in serious writing projects, I think in terms of paragraph and character styles.

My experience has been that styles work brilliantly in shorter Word documents, but fall apart in longer, more complex documents -- no matter how careful I am. Even my most complex documents are not that complex: I rarely use more than five paragraph styles in a document: Normal, Heading 1, Heading 2, Heading 3, and very occasionally, Heading 4. For academic writing, I use my own style to indent quotations.

Furthermore, there has been a longstanding bug associated with Word styles. Starting in Word 2007 or 2010, using styles "breaks" undo. I still don't know how to replicate the problem, but it's happened to me many times: I apply a style, change my mind, and press Ctrl + Z. The undo stack is still there, but Word has "forgotten" the style changes. I know of two fixes: 1. Go through the entire document and reapply EVERY style. 2. If the document was saved not too long ago, exit without saving. It's sometimes faster to recreate updates in a document than to reapply styles.