Do you think you can generally trust a random player to not not cheat by reading an adventure in advance?

A lot of games come with a sample scenario or two in the back that functions as an introduction to the game. If you start a new game of some kind (something more obscure I mean, not like Pathfinder or whatever) and intend to run the sample scenario as an introduction to the game for everyone, the other players are going to have every opportunity to read the adventure and know what happens/what they have to do. There's not much you can do to prevent his, not if you expect your players to know anything about the rules when you start anyway. All you can really do tell them, "hey we're going to play the sample in the back. While you're learning the rules between now and gametime please refrain from reading it." Do you think your ordinary, random PUG player that you've never met before can be trusted to be honest and not read the adventure?

No. That's why I make mine from scratch or take a published one and rework it. I've caught one player trying to cheat, thwarted by the new changes.

Personally, i dont think it matters if players have read the introductory adventure, especially if the goal is to gently introduce them to the game while they are learning the rules. You could give players the complete adventure to read, and then play them through it! Besides, jJust because they know what to expect doesnt mean everything will go their way. 

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