My rationalization of the "in melee" penalty derives from countless movies and shows where two people are fighting while another (usually the girl) finally wakes up and gets the gun, but when she tries to shoot the bad guy they are so back and forth and twixt and between that she either almost shoots or actually does shoot the hero by mistake.
Clearly this gets much worse when they are actually positioned so that the hero is between here and the bad guy in main body sense.
The -4 comes from a desire to avoid hitting the "back-n-forth" overlap that spradically occurs from even a side view of a melee. That shot aimed at the bad guy's shoulder might well see the hero's arm suddenly interposed on a lunge.
IF i were inclined to allow the "so what if i ht my buddy" i would still provide the penalty, as a form of cover, and use the cover rule to show attacks hitting the hero.
After all, even if the arrow is stopped by the hero's plate mail or inertial barrier, it still was blocked by the same barrier or armor and thus could not hit the bad guy.
So allowing the attacker to decied to trade the precise shot penalty for cover, at something like 2 to 1, so that ignoring the -4 produces -2 cover instead, might be an interesting house rule.
Clearly this gets much worse when they are actually positioned so that the hero is between here and the bad guy in main body sense.
The -4 comes from a desire to avoid hitting the "back-n-forth" overlap that spradically occurs from even a side view of a melee. That shot aimed at the bad guy's shoulder might well see the hero's arm suddenly interposed on a lunge.
IF i were inclined to allow the "so what if i ht my buddy" i would still provide the penalty, as a form of cover, and use the cover rule to show attacks hitting the hero.
After all, even if the arrow is stopped by the hero's plate mail or inertial barrier, it still was blocked by the same barrier or armor and thus could not hit the bad guy.
So allowing the attacker to decied to trade the precise shot penalty for cover, at something like 2 to 1, so that ignoring the -4 produces -2 cover instead, might be an interesting house rule.