This is probably not a discussion we want to start. While Python may have a small performance edge, it's nothing to get excited about. Likewise, the OP makes performance assumptions that may not be realistic. As I thought everyone knew, there are quite a few variables that go in to overall system performance. Database, caching and coding optimizations are as important or more than how the framework works.
That said, Massimo and the group have demonstrated a commitment to performance so if you have any specific recommendations or, better, code, I'm sure they'd be happy to consider.