As far as I understood, the "karmic dice" setting should "smooth things out".
My understanding of karmic dice was that one of its purposes was to reduce misses. At the start of EA, the steam forum especially was filled with posts expressing frustration about missing a lot. Because of this, to me it makes sense to have it on by default. More options are always good, though, if some want the option to have it on just for dialogue. There will also be difficulty options in the final game for people to adjust as needed.
