That's a really big answer to a pretty simple question, which is that without incentive, the banks may not shorten the timeframe to actually apply payments to credit cards because it is very profitable, and likewise for a small business when they're receiving payments from the banks. For the banks to drag their feet means the small business's line of credit is outstanding for an extra couple of days, which means the bank is making money on money that should rightfully be in the bank account of the small business.
I'm just suggesting that there is no incentive for the bank to speed this process up, as Mr. McKay has argued.