I'm no Xbox owner but maybe he did it so it would run cooler,last longer,quieter or maybe he wanted to see if he could do it.
He said:
"Right now, the primary goals of this modification were to A.) See if it could be done. B.) Better overall cooling C.) See if it could be done. D.) make and extreme modification without permanently altering the Xbox console E.) See if it could be done F.) Having a finished product that had a professional look and feel to it. G.) and of course...to see if it could be done!!!!"