Slow pitch arch

Question
I play in a league where they allow the pitcher to stand anywhere from the rubber to 2nd base.  He as to be in a straight line from home to 2nd. ASA league.  The league does this for the pitchers safety.  My question is this.  How can a pitcher throw 12' or under from 2nd base without increasing the speed?  Is there a "speed limit" in slow pitch?  

Answer
No speed limit is defined in the rules. The only requirement is a legal pitch is delivered with an underhand motion at a moderate speed with a perceptible arc of at least six feet from the ground and no more than 12 feet at its highest point above the ground.