[Rockingham]

Much of the reason for clearinghouses is that there is a residual and irreducible risk of error, fraud, and bad faith in financial transactions. The clearinghouse is there to avert and resolve those back office issues by gathering facts and applying skilled human judgment so as to resolve problems and claims quickly and fairly.

Massive transaction volume can overwhelm the back office operations of stock traders and clearinghouses. If that happens, the entire financial system can seize up and then collapse as the public loses faith. Whether that risk is present now is hard for even high level insiders to determine.

[aquila48]

“The clearinghouse is there to avert and resolve those back office issues by gathering facts and applying skilled human judgment so as to resolve problems and claims quickly and fairly.”

It’s considerably more than just applying “judgement” - it is their job to insure that both sides of the transaction have the necessary funds/assets (plus margin) to cover the transaction. They’re like the escrow company in RE transactions.