An opus' handicap, or just cap, is an estimate of a twistor's yield. It is formulated as the ratio of the tab divided by the quantity of wagers (cap = tab / bet).
This number constitutes both the couponholder's earnings as well as the house's payout. The cap is essentially placing a safe limit on the calculation derived from the above formula. Anything over the cap qualifies for a bettor's dividend, and anything less than the cap constitutes a loss for the juker/gain for the house.
Note (+): Losses here are absolute; bettors retain zero cash.