If Your model is NAND one, yes; and if xRegistry.sys users cover up users on HDD. On NORs, the same plus if your fw hasn't changed since HDDs swaps.
However, there is here some unknown factor. Disks are assigning in xRegistry and somewhere on flash (hdd s/n + hdd fw version). In theory, if you put not yet assigned disk, console will not recognize it and want format it. For some reason, for some ppl that's how it works I described in first sentence, but for others is impossible due to this assignment checking.
This makes disks swap reports inconsistent. And no one ever really investigated that (maybe some syscon flag deciding about that?).
Keep in mind that I do not misleading PS3 environment formatting disk with its assigning. Two different things and by written all that above, I assuming that all disks for swapping has been already formatted and encrypted by target console keys.