I exp a lot as well, and parse and save just about every PT. I'm pretty sure it's just in his head and it's all about the attack speed.
NIN and MNK do tend to get a lot more swings then even Ridill WARs with haste builds, sometimes by large gaps. In addition, NIN and WAR tend to just flat out double attack more often because of how much faster they swing (by that I mean like, 10% of 1000 attacks is larger than 10% of 500 attacks).
It's just attack speed creating the illusion of having a higher DA percent.
EDIT: Example parse just to illustrate how big the difference in total # of swings can be.
http://img324.imageshack.us/img324/7...vthfwartx8.jpg
Looking at the M.Ht/Ms (amount of hits/misses), the WAR/NIN using Man/Joy with 2 DA merits and Brutal has a total of 1119 swings, while me as a NIN/WAR using a Brutal had a total of 2485 swings.