There is absolutely no chance the American did not know what he was doing, as  the amount of top-level GM games in the line is growing exponentially this year!
1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... f8b4  4. g1f3  4... e8g8  5. c1g5  5... c7c5  6. a1c1 A topical,  sharp anti-Nimzo line. 6... h7h6  7. g5h4  7... c5d4  8. f3d4  8... d7d5  9. c4d5  9... g7g5  10. h4g3 To which Nakamura  replied without any hesitation with the novelty: