Hmmm... so if I get what you're saying, weapons with a low rate of fire and long range (like missiles and advanced torpedoes) are really sort of like a damper field that blocks half, two thirds, or three quarters (depending on if you're using fire rate 2, 3, or 4 weapons) of damage, because you only get shot at by the rate-1 weapons when you move into range...
Of course that wouldn't work when the enemy has faster engines, but then for assaults against satellites, bases, and planets...
