Normally you have one user of the contract who invokes it, and somebody else mines/computes the results. I think the trick here is that the user of the contrac

Normally you have one user of the contract who invokes it, and somebody else mines/computes the results. I think the trick here is that the user of the contract is also mining/computing the smartcontract at the same time, and thus knows the contract's results before it's published to the network. If they are unhappy with how the contract unfolds (because of the random component), they just pretend as if it all never happened, neither the contract usage or the contract mining/computing never took place.