Umm, I think it's pretty obvious that I said that he was claiming that if it were a Concordia, it would have to be a pretty poorly drawn one, and thus is obviously a Tarawa. And that he never claimed that the actual art was poorly drawn (unless, indeed, it happens to be a Concordia). If you look at the context, he's clearly arguing in favor of the cover art being the Tarawa, not the Concordia.
I'm not sure why you're being so argumentative, since as far as I can tell, we're on your side of this.
As for why the Tarawa looks somewhat like the Concordia, my argument here is that Confed had a certain style of carrier design, and when they converted the Tarawa, they used the same elements. Just like the Cerberus used EM catapults like the Midway, and the WC3/WC4 carriers had the fly-through covered flight deck. It's just a matter of the prevailing carrier flight deck technology at the time; when the escort carriers were being converted from transports, the open flight deck is what they were using.
Actually, the way I've heard it explained, the WC3/WC4 carriers are really just descended from the WC2 designs, with the exception that the flight decks are now covered (to defend against the 'Kilrathi kamikazes have disabled the flight deck' scenario so common in WC2

). In a way, even the Bengals are a sort of ancestor to the WC2-4 carriers, with their open landing deck/hangar.