I just don't feel that that is a way to increase students' learning fully. They may learn a lot, but they may also forget a Iot very quickly. It's a philosophy that fits today's globalized world. If different people learn to work together in the classroom, then I believe they will become better citizens of the world. It will be easier for them to interact positively with people who think differently, not only on a local scale, but also world-wide.
Collaboration is everywhere.
China has opened its borders, North and South Korea are on speaking terms. Collaboraton is the key to becoming a more complete person. Let me give a practical example of that. Imagine 25 students studying different topics. They will surely find some information that the teacher doesn't know.