Before revision:  We show the startling main result that under the standard BS option pricing model, this measure of relative value is a function of delta only and is independent of the time to expiry, the price of the underlying security or the prevailing volatility used in the pricing model.
After revision:  We show the startling main result that under the standard BS option pricing model, this measure of relative value is bounded by a simple function of delta only and is independent of the time to expiry, the price of the underlying security or the prevailing volatility used in the pricing model.