I have a ~500GB Time Machine partition I'd like to shrink slightly. My internal source partition is around 400GB.
Resizing the partition would be extremely slow, since Disk Utility has to check all the hard links Time Machine is using behind the scenes. On the other hand, simply wiping it and backing up again from scratch would also be extremely slow.
Is one or the other generally going to be faster? Is there some disk size tipping point at which it becomes more economical to switch strategies?
(I'm using an SSD internally and a spinning hard drive externally, connected over USB 3. Both the source and the destination are encrypted. Also, I have a second backup disk, so if I wipe and back up again I won't be temporarily unprotected.)