That actually gets around my questions above nicely. Moving Mjølnir ≠ using Mjølnir. If the hammer can be moved by natural forces, it’s just a chunk of metal - it won’t have the devastating impact it does when Thor throws it.
And I guess if Thor woke up and called the hammer back, it’d go regardless of natural forces acting on it.
Ah, I didn’t know there have been things that prevented the call from working (aside from the whole fall from grace storyline). I guess that’s why I stopped reading comics. No consistency 😂