the first fort i made that was really huge and had hfs had a mayor with this trait. she was my original expedition leader/broker, and i had her legendary in like 5 different proffessions. when i released the hfs all her cats were hunting in the lower levels and got slaughtered, along with quite a few dwarves due to my miscalculations.
she tantrummed over and over again for a straight year, getting unhappy thoughts for killing dwarves who came to talk to her and a few of her remaining cats. she also took down and killed several members of the fortress guard, who were wearing steel/adamantium plate and chain and were mostly legendary wrestlers. when they finally got her chained up she finally committed suicide by attacking one of my elite military hammerdwarves, who hit her back with his adamantium hammer and turned her into chunky salsa.
she also got a fairly respectable skill in throwing, and destroyed quite a few buildings. it was quite astounding. never had a problem with her till that point, she was a great mayor, she occasionally got happy thoughts from yelling at people and never made any annoying demands.
making such dwarves into military may not be the best idea, if they do tantrum more easily and often, they are likely to cause an amazing amount of damage. an unarmed dwarf beating several trained and armoured wrestlers to death is not something i ever expected to see.
there are risks if you are trying to train a thrower though. once the mayor had killed enough of her cats and one of her friends during a tantrum she graduated to insane shortly before she got hammered.