To heave to...you need to balance several forces acting on the boat. The first is the main sail adjustment which is trying to force the boat into the wind, the second is the backed foresail which is keeping the boat from tacking and the final adjustment is the rudder which is trying to turn the boat into the wind. Now if hove to is defined such that there is no forereaching then I question why the rudder is even necessary, since there must be movement through the water for the rudder to have any effect. You need the rudder to hold you in the hove to position. That movement through the water is a combination of leeway and forereaching, but there is some forereaching never the less.