Earlier quoted context omitted.
We've considered things like that over the years, but I think these and similar ideas suffer from a common flaw: people who disagree about X would disagree about reasons for upvoting/downvoting X or the level of "epistemic strictness" re X. So you'd just get the same arguments repeated at a meta level, which would not be a win. I'm sorry to sound so dismissive; it's at least partly because I'm writing hastily. I don'…
re: epistemic strictness You don't think HN users are capable of realizing when they are engaged in mind/future reading, even if it was an explicit rule ? You surely know the userbase better than me, but this seems unlikely. If you want nothing to change, so be it, but the idea that functionality changes cannot have an effect is very frustrating.
One can imagine a user saying something like "Although I personally am against nuclear power, since this is the 'optimism' thread it isn't the best place for my counterarguments so I'll post them in the 'pessimism' thread instead". However, such people are so rare that statistically they may as well not exist.