The periodic cancellation of all debts thing was one bit that I found fascinating and wished had been expanded upon. I mean, what actually happened historically after that?

I mean, did the credit market dry up overnight? Once the precedent has been set that the king can cancel everyone else's debts for no reason, what reason would anyone have for lending money? Or did some folks come up with "un-cancellable" debts which are deemed not to be cancelled in jubilees (under penalty of private leg-breaking)?