I'm not taking sides here, and throwing the rulebook at me isn't helping to solve the problem.
The filtering suggestions was the first example technological approach to solving the problem that popped into my head. I agree that there's a danger of fragmenting the community with that sort of change, but filtering out '-TSA' is hardly the equivalent of having a 'TSA sub-HN'.
Regardless of whether the filtering idea is good or not, I'd like to see more suggestions on how to fix the problem.
If we're going to "- TSA" filter the site, I'd be happy if 'pg just fired up a REPL and did that to news.arc.