I would agree that negative karma could be used for "evil" if it were made widely available on an account by account basis. Aggregate information could be made publicly available however. But tracking wrong action can be as important as right action..as long as you are prepared to use that information constructively to inform your process adjustments. I would shy away from making it a Canonical-only set of information and more of a leadership sensitive information for both external and corporately sponsored leadership.
What you don't want is bad practises going on for so long without a way to address them via normal process feedback resulting in developers like Colin feel like they need to make a public statement about the problems. I doubt he enjoyed putting people on the spot, but if triagers are making more work for him and other developers..that's a real problem. The developers are the critical resource, everything else needs to be tuned to help them be more efficient. The sort of statement Colin made is a red flag moment indicating the the processes aren't working. It draws attention to the problem but it has too little detail to know the scope of the problem.
The first step in addressing any problem is being aware of a problem. Negative karma would just be one way to seeing human process problems develop in a systematic and unbiased way. If you think its worth discussing more, feel free to write it up in Brainstorm and see if anyone takes notice. I'll even let you take credit for the idea.