Sorry. You put the nut back - you don't leave them turned. It's just to test for even loading (not very accurately but you're looking for one nut with almost no load). If one mount has sagged, the engine can sit on three mounts at rest and look quite normal.
Also, if the mounts are 10+ years old it wouldn't be a bad idea just to replace them.
Also, if the mounts are 10+ years old it wouldn't be a bad idea just to replace them.