Not for docs of any substantial size or complexity. While in the abstract it may sound like a good idea, you rarely want every element of a document to change in unison. Styles in Word, like stylesheets in HTML, are meant to cascade within related groups. For example, styles for the content of tables would probably want to stay single-spaced and unindented even if you changed the style for regular text to be double-spaced and first-line indented. If the table styles are based on Normal and you use Normal for regular body text, the table styles won't stay put when you do that. There are other (often more maddening) repercussions; this is just the most obvious. Admittedly Microsoft has done a terrible job of documenting the proper use of styles; but they are the single most important concept in managing document format issues and deserve more attention than they get.