The original soundtrack lacked any emotion. This is not the original Duel of Fates from Episode I, either. It's a different variant and I thought it fit in perfectly with the fight.
Hm? I mean, I imagined it would be fairly obvious. The moments that flashed were moments of weakness for Anakin - moments where he failed as a Jedi. These are struggles that Anakin will continue to face for the rest of his life, so having that parallel with the fight shows both the physical and mental conflict. There's no chemistry between Dooku and Anakin to establish a deep emotional fight on its own merit, but recalling the earlier film and Anakin using those darker emotions to fight Dooku is significant. Just as Dooku cuts Anakin's arm, Anakin cuts down a Tusken Raider, completing his failure. I thought everything linked together rather nicely and was proud to see how it ended up. I guess it's not for everyone, but this particular fight is easily the most criticized fight in Star Wars, and justifiably so.
Anyway, other thoughts from other people (lol)?