Um yeah, I can count. I was talking about data on the actual game disc. Vampire Killer appears a total of 10 times, the unused copy of Beginning appears 7, and they have the DXC Dance of Illusion on there 9 times. Slash, Iron Blue Intention, Mad Forest, and one of the game over jingles all appear twice for some odd reason. That's a LOT of extra data and the only explanation that makes sense is that the first three at least were used in a beta mode (which if the data is on there, it's probably accessible through pro action replay). I don't know why you'd need two copies of the others.
So those MP3s on there ARE exact duplicates. CRC checks of the original data files are the exact same. MP3 is a lossy format so when he converted them from the original files, of course it produced different file sizes, even though the compositions are exactly the same. The only two that are similar are BGM40 and BGM16.