Back to the original question.
Is there a way to mitigate/eliminate the damage a fellow PC takes from an ally's missile fire into melee.
Timeron Malachi probably got it right with the easiest method - simply have the archer step to the side. He doesn't really have to get to the other side since in order to provide cover the "line rule" applies (see the figure notes on pg 151 of the 3.5 PHB. Pretty much if you can't draw a line from square where archer is firing from through the ally then no cover and all of this is mote. No need to even get into the details of the optional striking cover rules if no cover is being applied in the first place.
Is there a way to mitigate/eliminate the damage a fellow PC takes from an ally's missile fire into melee.
Timeron Malachi probably got it right with the easiest method - simply have the archer step to the side. He doesn't really have to get to the other side since in order to provide cover the "line rule" applies (see the figure notes on pg 151 of the 3.5 PHB. Pretty much if you can't draw a line from square where archer is firing from through the ally then no cover and all of this is mote. No need to even get into the details of the optional striking cover rules if no cover is being applied in the first place.