How would Harrenhal reverting to the crown from 131-151 work, exactly? The crown doesn’t have a standing army able to garrison it. And I can’t imagine they’d let it sit empty for two decades, lest it become a haven for outlaws or get taken over by some up jumped small lord. Would the Tullys be responsible for appointing rotating garrisons? Even then, I can foresee problems, i.e. some commander holding the castle for a few years and then thinking he’s entitled to it.