So? More than 60% of trains aren't going to GCM. More than 70% probably shouldn't be. As far as I know, that leaves a safe margin of 40% for extra repairs, issues with the cars, etc. If the fleet was that bad to begin with, then that's the issue, not the GCM tunnel. People are just using the outrage about misallocation to GCM to surface other debates.

This is not the issue. It's common to deal with loading gauge mismatches when you have multiple models on multiple lines. The A and B subway divisions aren't fully compatible. Countries across the world deal with this, even the ones who do it right.