If Shin showed up, there would be no reason not to show his pretty face. By using Gong Yoo to play that scene but not showing his face, the point is to convey Kyung Joon has grown up and asking us to imagine an older looking Shin’s face on that body. Maybe it would have worked better to have a completely different body actor play that scene, but that’s neither here nor there. Yoon Jae didn’t die (yay!), Kyung Joon went back to his own body (double yay!), and Da Ran and Kyung Joon showed us that their love story could miraculously have its happy ending by their reunion which was clear enough to show he could remember her but vague enough not to spell it out. They should also have said that there would not be a mutual switch, nor are they interested in dealing with the aftermath of a switch back. I felt like people kept waiting and waiting for switch back, and of course they would be annoyed and disappointed that episode after episode it never happened.