A long time ago in pg's "Stave Off The Decline" submission, tptacek suggested a "sincere flag" for submissions/comments that you could set so you get no karma for the post. At the moment, I wish it existed.
Edit: Add reference https://news.ycombinator.com/item?id=2404027
tptacek was shooting from the hip that day, and posting a lot of his ideas (and regular annoyances), one per post, in rapid succession, but without the time needed for a lot of planning or analysis.
His idea of "sincere flag" could be improved by combining limits and disincentives to prevent high-karma accounts from just always setting the "sincere flag". There could be the usual limit of a karma threshold for the feature. There could be a limit on how many times or how often the flag could be used. There could also be a disincentive such as making each down-vote or flag cost a lot more (10x/100x/1000x), or making the use of the flag cost something substantial like -X% of all account karma.
With the right combination of limits and disincentives, his idea might work, and only be used on special occasions rather than be (ab)used constantly.
The most obvious effects of karma, that downvoting blanks out a comment, that you can downvote at a certain threshold, and that the threads are sorted by karma, don't require actually being able to see the number assigned to a poster.
As luck would have it elsewhere on HN I am hemorrhaging karma at the moment for expressing an unwelcome opinion. I am not ashamed of the content or the manner in which I expressed my opinion so I have no intention of deleting my comments. As far as I am concerned by clicking the reply button I am implicitly stating that my comment is sincere. It seems that HN could introduce an implicit sincere flag if commenters did not get a refund for deleting karma-negative comments.
Unpopular opinions are always tough situation. Part of the problem stems from "up" and "down" votes meaning different things in different contexts. For example, up-voting a submission is a way to say "thanks" for submitting it. This usage is problematic since the opposite of "thanks" really doesn't exist. The typical negation "No Thanks" is not strong enough, and "flag" is far too strong. For submissions, there is no down-vote. In contrast, votes on comments are often used differently, such as an up-vote being used to show "agreement", and a down-vote being used to show "disagreement". The contrasting usage of votes results in both user-centric context and submission/comment context influencing what each vote means.
No, it's false.