Allocating the uncertainty budget in currency issuance

The S&L may be programmed to operate within a 3% variance in its gains and losses.  But most of the flow is from loans to deposits. A 3% variance lets the currency machine issue at a 2% rate, nothing wrong as long as we have equal access and free entry and exit. When the currency machine nears the outer bounds of variance, rebalance of the two stacks with interest swaps implemented.

Once you have the HFT, then you automate, too late to turn back.

But auto cash is a break thru, the banker now makes his money via the ad and human interaction space, signing and uunsigning the customer to different sandbox contracts, directly helping to smooth inventories everywhere. The banker makes buck, a steady commission stream, mainly because gains to scale suddenly appear everywhere.