In this scenario, if USDT drops low enough, might you not have trouble actually procuring enough USDT to payback and unlock your BTC? It would seem like a sudden collapse of USDT might cause a complete stop in all trading of USDT pairs, no? I suppose you could counteract that a bit by continuing to hold a certain amount of USDT, but would the loan instrument still accept USDT as repayment if USDT becomes worthless?