Originally Posted by
blunk
To some extent it draws your attention from the game, I think that was the reasoning.
Poisoned monsters dying offscreen do not give any indication except xp gain if you have the option on (or maybe some thudding sound if you have enough Listening or Perception points).
I typically turn it on because it acts as a nice attention filter -- if you are fighting surrounded by a whole bunch of weak monsters, unusual symbols '[', ']' and '+' help to identify really necessary information. It also allows you to track xp gains early on without having to look at the bottom of the screen.
Speaking of which, I'd be happy to use extended damage indicators ("-foo- hits you for -x- points of damage) in ASCII and fading combat numbers in tile mode.
I like my women like my ADOM loot - hunted as treasure and in extra quantity.