And the idea of deliberately trying to hide information just feels wrong. It feels like Dark Arts.
If by 'dark arts' you mean 'non-rational methods of persuasion', such things may be ethically questionable (in general; not volunteering information you aren't obligated to provide almost certainly isn't) but are not (categorically) wrong. Rational agents win.
I like the way steven0461 put it:
...promoting less than maximally accurate beliefs is an act of sabotage. Don’t do it to anyone unless you’d also slash their tires, because they’re Nazis or whatever. Specifically, don’t do it to yourself.
It has been claimed on this site that the fundamental question of rationality is "What do you believe, and why do you believe it?".
A good question it is, but I claim there is another of equal importance. I ask you, Less Wrong...
What are you doing?
And why are you doing it?