Yes, the line distribution of CMIYC is the best part (Which is kind of irrelevant in what makes a good song or not, so take that with a grain of salt.) The inventive and refreshing choreo is cool too (Again, irrelevant). The "I'M GOING TO FIND MY HEEEEEEEAAAAARRRRRRt" is the only musical standout, like I'm like "YAAAAAAAS BITCH, I'm going to find my heart too!" when I hear that part, and I'm running over plains and jumping over valleys and stuff, and then when I finally think I've found my heart, the drop hits and I stumble and fall face first in a humongous pile of buffalo feces.
I'm an idiot for finally realizing Jess's parts in Catch Me If You Can… I'm sure someone said this already…
Yuri's part in the first chorus
Yoona's part in the second chorus
Both of Sooyoung's parts in the bridge and final chorus
The line distribution wouldn't have been so terrible, still…
Yoona's "I'm going to find my heart" was Jessica's. Taeyeon's "ohhhh" towards the end of the song was also Jessica's, it sounds exactly like an adlib she would do.
