The Normal style is definable just like any other style. It isn't dependent on any particular template BUT if you choose to import/refresh styles from any template then it is likely that the Normal style will be updated - that is the point of importing styles after all.

Just make sure that importing of styles doesn't happen when you don't want it to. This means you should never tick the option in the Templates and Add-ins dialog to "Automatically update document styles" since this refreshes styles every time you open the doc (and other users may have different templates).

As I said, this is really no different with your own custom styles - if you choose to import styles from a template, and that stylename exists in the template, then that style definition may change. The Built-in styles always exist in every template whereas the custom styles might exist in a template.

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Andrew Lockton
Chrysalis Design, Melbourne Australia