I'm not sure where the contradiction is. The key to me is "which places a high academic standard and holds teachers accountable", which I equate to "rigorous training". I guess the difference is on how we define "talented". To me most kids are just educable, which means they don't constantly push themselves, they don't take initiatives to dig deeper, nor do they proactively find resources to do more. Or they struggle without careful guidance. Yet they can make leap and bounds when they experience a rigorous program. These kids need nurturing from the teachers. At least that's my personal experience: I was content with my performance, until the problem sets showed that I was not really as good as imagined. Also, I believe that training makes a big difference to people of similar level of talent. That is, wealth can't push a kid who struggles with Algebra II to understand calculus, but may well help a student with sufficient talent to stand out. My personal experience: I went to college, didn't have the drive to push through the tomb of Demidovich. And then my friend got me a much shorter book for challenging problem sets in Analysis. With his help I finished the book, and man, what a difference it made. I stayed top of my class and became a TA on calculus in my sophomore year.

I wish I could find it, but unfortunately it was likely ten years ago. The article left a lasting impression on me, though, so I repeated it once in a while in different context, at the risk of totally rewriting what actually happened.