I just find it sad that every time I see this topic, people automatically assume that someone must be cheating to get high scores. Granted, it's statistically improbable that someone would roll an 18 result 6 times in a row, but it's not impossible.
I've got a friend who, when he rolls really good stats - say, more than 3 16s in a set - will reroll to get something lower. He was burned by cheaters years ago, and now would rather discard a really good set than risk having his friends think he might have cheated. I think that's just sad. :\