It appears he wants to correlate the number of comments with their contextual value, though.
A better indicator of how trollish a thread is and how much that's getting in the way of the conversation (because those are two different things - users may be willing to put up with vehement discussion in one instance but not another) would be the ratio of downvoted comments to comments. I can even see measuring the length of comments and the depth of a thread, as a deep thread with lots of tiny comments might be an indication of sniping.
I realize i'm probably being incredibly naive and that the whole thing is complex with multiple factors interrelating but I don't see how the ratio of upvotes to comments tells you anything useful, if it doesn't take into account that people may comment without upvoting, and people might upvote bad comments. I make certain to upvote the article now with every comment because i'm aware that not doing so, regardless of the content of my comment, is an implicit downvote.
I think it's also a mistake to correlate "controversial" with "unwanted" but that might just be a matter of semantics.