Just to note, Plandex also has integration with git on the client-side and can automatically commit its changes (or not--you can decide when applying changes).
One of the reasons I think it's good to have the plan version-controlled separately from the repo is it avoids intermingling your changes and the model's changes in a way that's difficult to disentangle. It's also resilient to a "dirty" git state where you have a mix of staged, unstaged, and untracked changes.
One more benefit is that Plandex can be used in directories that aren't git repos, while still retaining version control for the plan itself. This can be useful for more one-off tasks where you're not working in an established project.
One of the reasons I think it's good to have the plan version-controlled separately from the repo is it avoids intermingling your changes and the model's changes in a way that's difficult to disentangle. It's also resilient to a "dirty" git state where you have a mix of staged, unstaged, and untracked changes.
One more benefit is that Plandex can be used in directories that aren't git repos, while still retaining version control for the plan itself. This can be useful for more one-off tasks where you're not working in an established project.