I agree altough their usefulness against heavy targets - as you said - could indeed be the crux of the matter. Does the GCS classifiy as heavy target? What I mean is that during a rather long engagment we see her only once firing the two main cannons which seems odd, why sacrificing a lot of the smaller ships if you could prevent it by just firing two, three, four times.Deepcrush wrote: The Negh'var wasn't meant to do anything but move those big guns around for use against heavy targets. While the Negh may not be as big as the GCS, her guns out class anything we've seen.
So maybe they have aweful long recharge times or other limitations which makes them mainly useful against stationary or semi-stationary targets. Sure, if they got a lucky shot it is over.
From all the fleets the Klingons have probably the most practical approach to war which is as it should be. So they have rather specialized ships and for ship to ship battles they already have the excellent vorcha's and bird of prey variants but they lack a heavy hitter against stations etc. This role would be filled by the Negh'vars and since their job is to bring down stations and ships far larger as themselves they might have problems facing a contemporary opponent of a similar tonnage alone.