This is one of my favorite songs to do karaoke to because I love singing the backup part in this kind of strained, god-awful falsetto. It really annoys the uptight karaoke professionals (you know the ones I mean.)
Dave,You'd have a blast at a karaoke box over here because there are no pros. Karaoke is something the Japanese generally do with friends and family. The only people I've ever known to practice are salarymen trying to get the pronunciation down for "Hotel California" or something.