(Per discussion on this PR https://github.com/jenkinsci/github-oauth-plugin/pull/35#issuecomment-90203532)

I've attempted to test the behavior of the user:email scope. I created a test user & org and deleted the user from jenkins via the delete_user() method in puppet_helper.grovvy between each test (note that Jenkins also needs to be restarted to clear caching). The user:email scope appears to have no affect on being able to retrieve a user's email address. Only changing the user's github profile to have a public email address worked. I don't know if this is due to GH's scope's, org.kohsuke.github.GHUser, or something in the plugin itself. I can say that adding user:email by default doesn't make any sense at this point.