Recently I made a bet with a matchplay coupon and got 10 v 8. I could double, but only my principle wager, not the coupon. I chose to hit instead. Was I correct in doing so? If I was correct to hit, what is the worst double we should opt to double with? Obviously 11 v 5 is a no brainer because there is nothing to lose, but something like 9 v 3 is probably a hit because this is already a close decision.