What new "duel" happens? Who wins? What are Alan's feelings in the end? What are Robins?

Duncan stepped in between and slyly challenged them to prove who was the best piper. The two men fell for this and began arguing over who was the best. Duncan brought out his pipe and Robin began. His tune was nice but uninteresting. Alan's tune improved upon Robin's and flowed into ravishing variations. Robin took his pipe and played Alan's tune note for note before illustrating his skill by reworking each variation to an incredible new height. Alan was forced to admit that Robin was more talented than he. After this point, the two ate, drank, and played through the night.