Magic Calculations

I realize there's some information on this on ffxi wiki already, but I'm hoping a dev will read some of this and give a few answers. In particular the 2.299 multiplier versus 3 or even 3.3 repeating on the -ja spells and tier Vs. My tests have shown the -ja and tier V spells to equal

((my int)-(mob int))*(2+(307/1024))+V, where V is the idividual spell's flat damage bonus.

*EXCEPT* for aeroja, which replaces the (2+(307/1024)) with (7/3). What the heck?

Tests are here: http://tinyurl.com/46qt6qn