Multiple cloned Time Machine drives safe to use?
 

Time Machine remembers changes made to your Mac since the last time it was backed up, to avoid having to compare everything each time.

After cloning my Time Machine drive, is it safe to use both in alternation?

SD does not copy the UUID, which is good, as that's a dangerous hack. I *want* Time Machine to do a full scan each time I "Change disk" in System Preferences. Will it? Or are there other identifiers that SD *does* copy?

It should do a full scan, garoomph.