The only reason it is in Athlete and Kalin's best interests to keep going in this war after Paris was succesfully taken, instead of consolidating and returning to builder mode, is because Byzantine have made it their business to screw over the Ottomans for the rest of the game at the expense of any chance of winning of their own and hence the Ottomans need to get a complete kill.
But maybe if Byzantine were willing to give up their petulance over losing their agggresive city and convince Athlete/Kalin that they won't embark on a ruthless vendetta, maybe they could convince them to leave them alone and get out of this choke. That's the only way I see them getting out of this situation and into one where they may be in some way competitive later in the game.
But maybe if Byzantine were willing to give up their petulance over losing their agggresive city and convince Athlete/Kalin that they won't embark on a ruthless vendetta, maybe they could convince them to leave them alone and get out of this choke. That's the only way I see them getting out of this situation and into one where they may be in some way competitive later in the game.