So, taking a step back from even the metaphor… to get in the groove is a term that was used by recording engineers when they were about to cut a record. If you were “in the groove” the record lathe was cutting the groove. Hence: “In the groove.”
I’m not cutting a record by any means. But at the same time, I really do feel that I’m starting to perform a lot better in the past week or so than I have in years.
It feels so good.