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docs/src/worktree_behavior.md

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+# Behavior Details
+
+When working with worktrees and GRM, there is a lot going on under the hood.
+Each time you create a new worktree, GRM has to figure out what commit to set
+your new branch to and how to configure any potential remote branches.
+
+To state again, the most important guideline is the following:
+
+**The branch inside the worktree is always the same as the directory name of the
+worktree.**
+
+The second set of guidelines relates to the commit to check out, and the remote
+branches to use:
+
+* When a branch already exists, you will get a worktree for that branch
+* Existing local branches are never changed
+* Only do remote operations if specifically requested (via configuration file or
+  command line parameters)
+* When you specify `--track`, you will get that exact branch as the tracking
+  branch
+* When you specify `--no-track`, you will get no tracking branch
+
+Apart from that, GRM tries to do The Right Thing<sup>TM</sup>. It should be as
+little surprising as possible.
+
+In 99% of the cases, you will not have to care about the details, as the normal
+workflows are covered by the rules above. In case you want to know the exact
+behavior "specification", take a look at the [module documentation for
+`grm::worktree`](https://docs.rs/git-repo-manager/latest/grm/worktree/index.html).
+
+If you think existing behavior is super-duper confusing and you have a better
+idea, do not hesitate to open a GitHub issue to discuss this!