The `efficacy' of the method of dispatch is, imho, judged by the rapidity of retirement from the target pool. A well aimed motor vehicle... But, most go stray with the swerve and, when picking up trash from the ditches along the road, I `volunteer' to end the suffering of those victims, still...
Cover trap. Carry trap downwind of house, turn on hose with spray head. Uncover trap, back up, holler. and take a shot in direction of trap. Skunk sprays, gets sprayed with hose. Finite amount of stink per skunk. Once `ordure' has been rinsed away, walk up and harvest skunk.