i wonder if the apparent aura secrecy around automissions is just my personal impression caused by not reading the forum enough, etc.
i have only read that availability of the automission option depends on the map being special in some unknown way.
what maps are special and what determines the results?
just my first thought would be that if player has completed (a few) recent mission(s) without losses, there would be the "free mission" option (= automission), which would complete the mission as victorious (without need to reload, and with no mysterious penalties to skills and loot, etc.) if the player does not feel like doing it manually (= the game is being nice to the player who has dominated some recent missions and does not put the player through the tedium of clicking to produce the same result).
but maybe i got it all wrong, and there is some deeper philosophy behind the automissions.
