Under a private system, the link between price deviation and correction is immediate and strong because supply is under the direct control of the currency issuers, who have the means through loan and trading operations to tightly clamp down on (or expand) the supply.
Third, a policy aimed at facilitating employee ownership: S corporation employee stock ownership plans (S ESOPs) are also a deviation from a pure income tax system, but the benefits of promoting employee ownership are broad based and well established.