New redux warning?

Hello!

We used react-navigation on a project a while ago, and integrated it with our Redux store as per the documentation. But I've just noticed you now have a warning telling people not to do this.

1. Can you elaborate why it's bad? "You probably don't need to do this" is a bit ambiguous.
2. Managing navigation through actions was our main reason for doing it; it meant one LOGIN_SUCCEEDED action would mutate both our app state and the navigation state to put the user in the right place. What's the recommended approach instead? Is it to navigate without the navigation prop?

Start with the Redux integration warning and the linked navigating-without-navigation-prop documentation. Review the issue's questions and existing wording, then clarify why the integration is discouraged and identify the recommended approach for navigation after an action; the documentation should answer both questions directly.