Maintaining one's temper as relates to civility and professionalism

Utah Lawyers Helping Lawyers supports the civility and professionalism movement in the law and presents continuing legal education seminars on these topics. If practitioners were more civil, LHL believes that they might experience less stress and consequently, fewer conditions which are caused by or exacerbated by stress, such as burnout, anxiety, depression, etc.
Part of being more civil and professional includes maintaining equanimity. In the practice of law, arguments may become heated. However, it is difficult to apply one's best legal reasoning if one's mind is clouded by loss of temper.
I found the below quotes which describe the importance of not losing one's temper at http://www.brainyquote.com/quotes/keywords/temper_3.html
"It is very important not to lose your temper in a courtroom, or in anything else you're doing," Warren Christopher.
"Keep you temper. A decision made in anger is never sound," Ford Frick.
"Men are like steel. When they lose their temper, they lose their worth," Chuck Norris.
"One should not lose one's temper unless one is certain of getting more and more angry to the end," William Butler Yeats.
"Temper is a weapon that we hold by the blade," James M. Barrie.