Oh no, people do say it like your example. I don't think it's the best way or the most complete way to say it, though.
Your way sounds like he didn't cheat, but he just let you cheat.
Since he cooperated and was an "accomplice", he cheated just as much as the other person.
The way I wrote it leaves no doubt.
Still, your way is an idiomatic way of saying it. I was just giving you another option.
AngelEyes