Indeed. His score was great when everything started and I'm sure his #otc ratings were a reason for people to trust him. In the end it has turned out to be pretty useless though. I mean, someone still gave him a rating of +10 in November; long after BST was dead and the cat out of the bag.
Given a number of sockpuppets any rating system can be abused to create false ratings. Not only can a scammer upvote himself, but also downvote others. Still, scammer tags do serve a purpose, especially for those with high post numbers. A newbie can be honest, but most would consider someone with an old account and lots of posts to be better.
A tag makes that account worthless. Just look at paybtc: he's ignoring everything, acts like nothing ever happened and doesn't even attempt to be helpful. He even changed his name a few times; I assume to get rid of the negative aura his old name has. Yet, he has no tag.