Like you said, that would be annoying
I doubt it adds much to the fighting aspect of the game. After all, all you can do in a fight is tell your characters who to attack and with what. It's not like you can say "my fighter attacks the left toe of the goblin" or whatever.
Not that it's a bad idea, but people would just reload if they don't like the effect. ADND in real life is just not the same as on the PC (sigh...)
It would be cool if your character started to talk like Minsc afer taking a headwound
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The last arrow of Legolas kindled in the air as it flew,
and plunged burning into the heart of a great wolf-chieftain.
All the others fled. -J.R.R. Tolkien, The Lord of the Rings