Excellent point and spot on.
I have my downers on Yaya but when he plays, he dictates the play and we boss possession and that's key tonight.
I suppose that is, in many ways, what it boils down to in terms of people's preference for selecting Yaya or not. My (perhaps somewhat pessimistic) view is that even if Yaya plays, we won't dominate possession - I fear that we'll still have too many technically-limited players out there to do so (Hart, Sagna, Otamendi, Mangala, Clichy, Fernando), even De Bruyne and Aguero, for all their obvious strengths, aren't the most adept at keeping the ball. And I can't really remember Yaya dictating play in many big games in Europe, to be honest? That's why I'd be tempted to leave him on the bench and use him as needed later on.
Not that I'd be in any way bothered to see him start, though - I don't think the question of whether he plays will, in and of itself, decide things.
And if he does play from the off, I obviously hope that he's fucking brilliant!