It was and it irritated me more when I failed to meet the requirement and had to REPEAT THE WHOLE SONG. Atlantica in KH1 wasn't so bad, although the controls were almost close to impossible.
I hope they put in The Lost Empire's Atlantica instead of Little Mermaid's Atlantica.
Atlantica the Lost Empire seems more of a fit to Kingdom Hearts than Little Mermaid's Atlantica. I hope there is a world called "The Lost Empire" in KH3, that would be so awesome.