quite a while ago there was a discussion about how to improve the usefulness of the style selectboxes of tinyMCE and CKEditor. As both editors parse stylesheet.css to fill this box with the defined classes, it is often cluttered with classes that are not intented to be used in the content (but instead for header, footer, wrappers etc.). Finally Gert came up with a good idea: add all styles that are necessary for the content to stylesheet.css, and put everything else to another stylesheet. Include this second stylesheet directly from template.htm.
Perhaps something to consider for template designers. Anyway, this might be a useful technique for users (particularly webdesigners).