kiai as in screaming at the other bugger until he/she craps in his/her/its pants then perform the softest technique that you can do? have not done that sort of thing since i got out of karate. i only scream like a girl when we do shinai work.
the most disturbing kiai that i encountered was from one of my sempai who laughed louder as you slammed him harder. very disturbing. i used to abject terror screaming, even whimpering screaming of sort, but laughing is just not right. just not martial, if you ask me. folks would think that we are some sort of comedy central or something. bad enough we, men, wore skirts and falling over ourselves, but laughing is just not right!