That feels a bit buggish because 8 sbc should be able to kill about 20 destroyer a turn.
Guess that depends on the exact combat algorithms, we can see attack and defence values but the details on just how they correlate to anything is a bit unknown. I know that 1 scout appears to kill cruisers every now and then, more often when the cruiser fleet is small, but even against a 100 cruiser fleet sitting at one of my planets, a 1 scout defence sometimes does some damage.
