@ TheDeadlyShoe:
I get the probability behind that.
I know turrets can be ahead, but considering the overhead of turret gear and larger fire controls, we'd need a rather specific volume of incoming missiles at a rather specific speed range. Likewise, the reverse where turrets do worse than usual (high volume of fire, excessive tracking speed) should be rare against a competent opponent... but I've seen a few things from NPRs that made me scratch my head
On railgun calibre: I agree that 10cm railguns are generally the most useful ones. Larger often don't compare favourably to small lasers unless we have impressive capacitor tech.
In fact, I stick to 10cm railguns more than you do. For a limited anti-ship capability, I don't increase railgun size, I add limited laser armament.
if our speed and fire control irange s better than theirs, a single 15cm laser can give us flawless victories. If we take turn fire: 10cm railguns become much more useful in a knife fight if something else carves nice gashes. I don't discount them in the anti-ship role, but prefer not to have to use them that way.
On CIWS: If combat damage and losing crucial systems is a consideration, I'd rather add redundant sensors/FCs than CIWS and still risk losing most of my point defence.
Fortunately, low-tracking high-volume weapons makes FC redundancy cheaper as well.
That said, regular PD not working at point blank range (in final fire mode) and CIWS working during jump blindness were news to me, thanks for pointing that out.
@ Erik Luken:
Of course, RP considerations trump everyting else. I tend more towards picking a weird doctrine, then min/maxing ruthlessly in its implentation... but having certain lines of tech dormant until you discover them in foreign designs sounds interesting.