Madison Square Garden chairman James Dolan responded to a Knicks fan who had criticized him with an email wondering if the man is an alcoholic and telling him to root for the Nets instead. An MSG spokesman confirms the email, which appeared Sunday on Deadspin.com , was written by Dolan, who is also president and CEO of Cablevision Systems Corp. The criticism of Dolan was sparked by the poor performance of the Knicks, which are 10-41 on the season.