The potential is clearly there, which the SP Forum takes VERY seriously. People wishing to trade through the SP Trade Forum have to go through a probation period so people can get comfortable with them. Item ID's are published, there is a list of items likely to be duped and hence considered untradeable, and people are stringently watched if they trade or MP. The attitude is basically, "Do what you like on your own computer, but if you interact with another forum member through multiplay or trading and are found to be less than completely legitimate, you will be instantly banned." Thyiad does a fantastic job at policing this in a professional and reasonable manner, in my opinion, as do the other forum members. I've seen a long time forum member get banned for inadvertently showing they had made a Silence runeword in a bow with the item level 99. The runes used were all apparently legitimate, but since 1) Hell Baal is the only critter who can drop ilevel 99 items, and 2) Hell Baal only drops magic, rare, set, or unique items, the bow was judged to be impossible to get through legitimate means and the member was permanently banned. In other words, cheaters are likely to slip up at some point, and the threat of banning acts as a powerful deterrent. (So does pride!)
I freely admit it's not to everyone's taste, but I hate to see it written off without just consideration. I would have stopped playing the game years ago if I hadn't moved to SP.