Ripple --
Even when the Interceptor theshold is exceeded, you still stop 1/6 of all interceptable fire -- a linear rate after a threshold is exceeded.
The GEG, however does not even possess a linear component; it's just a constant, per weapon system.
So, the GEG suffers a little worse from the threshold than the Interceptor does -- but it benefits from it at the lower PLs, too. 6 of this, half dozen of the other makes decent GEGs (GEG effective 2 for LR becuase of dodge) hard to balance at low PLs (balance done by a very very small gun), and hard to balance at high PLs (for the Cruiser --- it gets a huge R arc gun to try to compensate for a horrid defense system. Would rahter have just gotten more hits, see the Armored Cruiser Battle-level-idea-not-balanced-thing.)