It is I'm just talking from my own experience, I know many potentialy good players that are not as good because they are not flegmatic and calm, but more of a "where's the action" type of people (what a sentence ).
Anyways, not just chess players, I believe that no one should have highly volatile behavior in any case
Are you talking about Fischer?
Is he? I'm not as familiar with GM personalities as I probably should be
Hey lecterror, you can have a good start with this page bellow and all related subjects at bottom of the page there. Enjoy! http://en.wikipedia.org/wiki/Category:Chess_grandmasters
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