Several of the posts have brought me to thinking a few random thoughts.
1. There's a difference between *using* styles and *creating/editing* them. In the LyX/LaTeX world, as well as the HTML/CSS world, one is indeed forced to used styles (called "environments" in LaTeX speak) because that's the way the system works. The styles/environments are created by supposed experts who create document "classes," or templates. But, neither the classes nor the environments are easy to modify. The end-user selects the environment he wants (\chapter, \section, \quote, etc.) and then lets the program do the work. As one writer mentioned, it truly separates the operations of writing and typesetting/formatting. Markdown editors in the HTML world also allow such clean separation. None of the WYSIWYG word processors (Word, LO, OO, AbiWord, etc.) provide such a clean separation between editing and formatting. And, yet...
2. In the LyX/LaTeX world, it all works very well...until you want to modify a small formatting parameter for a specific paragraph. Yes, it can be done, but it's not intuitive, nor encouraged. Despite the advanced formatting capabilities of LyX or LaTeX, few writers use them, I believe in part because making even a small change from the default settings sometimes requires a massive on-line search for the right command to change.
3. In the Word/LO world, this case of the "one off" paragraph modification is where I see resistance to styles from end-users. I've got paragraph style for just about every possible situation, but there may be a single paragraph where a user wants to change one parameter. If the user doesn't understand styles, he'll just apply direct formatting to the paragraph, without creating and/or modifying a style. Thus, just having users write with templates and styles created by others will only take people so far. At some point in time, they will need to learn how to create and/or modify styles. Otherwise, they'll have documents with a mixture of styles and direct formatting, the beginning of what could grow into a mess. I believe AbiWord has (or had) a feature to "lock styles" meaning a person could be locked out of changing formatting directly. All formatting changes would have to go through styles. I'm sure it would be a maddening feature for the uninitiated, but it would encourage people to learn to do use styles in the "right" way.
4. Document collaboration is a real bugaboo. We lawyers share documents repeatedly. I would create a document using styles, and send it off to a colleague for further edits. I would get it back with a mess of styles and direct formatting. I see no answer to this conundrum, simply because our programs allow so many different ways of accomplishing the same tasks, and I couldn't expect a colleague to listen to my styles tutorial when all he wanted to do was make a small edit to my proposed contract.
5. I agree that LO's styles work much better than Word's. With LO, I can list my styles hierarchically, so I can change a parameter in one high level style and have it changed in all lower level styles based on the same higher style. (So, no, you don't have to change each and every style just to change the font throughout a document). Word has styles based on other styles as well, but I have yet to find a clean way to list them in the style box in a hierarchical manner.
Virgil