The piano is the X factor. People have a tough time following the structures when there's no piano there, spelling it out. It makes it more easily understood, particularly to people who don't know as much about music.

青竹 云海 晨光 星夜 荷风 晴雪 秋山 听海 沙丘 森语 梅影 花野 听雨 晴窗 暮色 橘光