If you examine the Mail directory structure for each mailbox there is a string of subdirectories ending in one that will contain the actual messages, if any. Are these intermediate folders actually search buckets for the search function in the Mail app? I have unsuccessfully tried to attach a screen shot from my machine, but can email it if someone will give me a destination address.
asked 02 Apr '12, 13:05
Mail.app uses the Maildir spec IIRC.
Think of it more like a filesystem with a strict naming hierarchy then an in-memory structure.
It used to use mbox, but they switched to individual files for each message for Spotlight compatibility.
answered 02 Apr '12, 13:47