[Scott Blakley]

I was having this same issue after deleting about 200bg. The solution I found was rather unexpected. I figured I would try restoring the deleted library from time machine, and then go into final cut and delete individual projects and clips from the library. However, the moment time machine started to restore my library, about 400 GB suddenly seemed to free up on my hard drive. I immediately stopped the restore and now I seem to have even more disc space back than I was expecting.