Better documentation related to repository order

I was not able to find clear documentation describing the order of repositories used during a build. For example, the documentation should answer the following questions.
1. Which repositories are used first, the ones defined in settings.xml or in the pom.xml or super pom?
2. The order of repositories defined in the settings.xml profiles seems to be the reverse of what one would expect when viewed in the effective-pom, why is this?
3. If a repository ID in settings.xml matches one defined in pom.xml which one takes priority?

Some additional information is available in the JBoss build forum.
http://community.jboss.org/thread/160185