I suppose it also helps in ggmod that even a Battlefortress dosen't tend to vaporize medium ships in one volley...
You get lots of action and slow crippling before they go down in flames.
Overkill is rarely an issue, and that 50% at double expected means you don't tend to waste any shots unless there is a lack of targets in range...
And with the ability to build 30 scouts per turn at a homeworld, and the whole fighters thing, that dosen't happen too often either