I don't agree at all that the margin would have been bigger for the following reasons. If McKay plays JSOS stays back and Young wouldn't have played. This would have meant Weitering on Chol which is a much better matchup for us than Young who was beaten convincingly especially early. I don't think there would be any significant change in your ability to rebound from D50. McKay is a very good pressure player for someone his height but let's put that aside. At the very least McKay provides a very clear aerial target. Makes it very easy for the smalls to know where the ball is going and they can be at his feet to stop the ball leaking out for rebounds from D50. It also means that we can play Kemp as the 3rd tall rather than the 2nd which is the role we envisaged for him when we sent him forward in the pre-season. The other thing it does is it allows McKay to play 2nd ruck rather than Young/Cripps. McKay is a much better ruck, gets him around the ball and around the ground he is elite.
I really don't see how McKay instead of Young makes us worse. In fact I think there are plenty of reasons why it would make us much better as described above. And before I get jumped on I'm not saying with McKay we automatically win or anything. But first two rounds I think we have gotten very little from two very important pieces to our team. This team hasn't played at anything close to its capacity yet imo.
So you've just proved my point.
Silvagni had 5 Tackles I50 (the most of any player on the ground, and probably some kind of record) and if you put him down back you lose that, including his 18 pressure acts, which is high for a forward (I don't think I've ever seen McKay get more than 10), and you lose a vital defensive-forward, which in turns means Hawthorn have an even easier time transitioning from D50.
But I can see why Carlton people don't value forward 50 pressure that much.