I don't know who started that rumor...possibly Mustang & Fords (??), but the Versailles does not have a fixed rear caliper that would cause the rotor to crack. I've had two Versailles, and know for a fact that the calipers are "floating units" and not fixed. --they are setup just like the (Granada-style) front calipers --as floating units.
If the rotors were cracked, it's because someone overheated them or ran them beyond their minimum thickness limits, or possibly from not coating the anchor plates with anti-seize, so the caliper could move as the pads wore down.
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