So how does this thing work ?
Let's say that "Surge" the sammy with Granite Shell got a hit from AK-97 (10DV, -2 AP), and he has Armor Vest (9) on him. We've got the situation where:
AP cuts both the Shell and the sammy's Armor ((4-2) + (9-2)) = 9 dicepool + 1 success
or
AP cuts only the Shell, but "does no harm" to the armor ((4-2) + 9) = 11 dicepool + 1 success
or
AR cuts only the Armor, but "does no harm" to the shell ((9-2) + 4) = 11 dicepool + 2 successes
Which one is correct?