Hugh Mann wrote:
Once the Romulans intervened, the war began to go quite well for the Federation (culminating in the successful invasion of Chin'Toka, which the Dominion couldn't even afford to properly defend with an actual fleet, relying instead on the orbital weapons platforms that proved unreliable and mostly useless compared with a proper fleet) until the Breen intervened in turn and rendered 2/3rds of the Allied fleet strength useless.
Yes, I think Christopher somewhat exaggerated the bad position the Federation was in (I actually think DS9 is interesting in that it showed the good guys having a slight upper hand for a large part of the war) but that doesn't change his broader point. Your whole position hinges on the idea that the Dominion sent most of it forces into the AQ and that idea is simply illogical both from the perspective of what we know about the Founders and the perspective of simple strategic common sense. To sum it up: The Founders are hugely paranoid. The whole reason they set up the Dominion was to protect themselves. They have a huge territory in the GQ to control and protect from rebellion. They probably have neighbouring powers in the GQ that they consider a threat (for all we know, they might have been leading ten parallel wars of conquest in the GQ while "our" Dominion War was happening). Even if they had no current threats in the GQ, surely they had to consider the possibility of a new threat arising (to go for the classic example, a Borg attack). The Founders are risk averse, slow and methodical, long term thinking. With all that, the idea that they would send most of their military to a distant part of the galaxy to which they are connected only through a single choke point that can always disappear (however small that posibility might be), simply doesn't make sense.
As for Dukat, I think he deluded himself into thinking the Dominion would have allowed the Cardassians to basically run the AQ territories and hugely increase their own power. And once the time was right, a few well placed internal sabotage actions (block the wormhole, take out the ketracel white supply) would have left the Cardassians in a position to challenge the Dominion forces in the AQ. All in his mind, of course. There's no way the Dominion would have allowed any of that.