Regarding Magic Accuracy:
Tested using Lv1 Corroded Coblyns and Lv15 Moiling Moles both outside of Ul'Dah. I would gather ~10 of them together on 50 THM then AoE Blind, Slow, and Paralyze every minute. The goal was to find the "land rate" cap. This cap was 95% in XI, meaning no matter how much more MACC and dLVL you had over a mob, you would still miss 1/20.
Results as follows (ty Tachikoma for the wonderful parser)
http://img402.imageshack.us/img402/4306/macctest1.png
Couple things from this:
(1) There appears to be a cap on "land rate" of roughly 75%.
(2) The cap is not increased by the 8-man party bonus.
(3) Max # of mobs you can target with an AoE is 8.
Because these tests deal with low level mobs at the apparent land rate cap, these tests show nothing regarding how the MACC and MND stats change the land rate (for instance, trying to answer the "which is better?" question).
Overall pretty disappointed at how low the land rate cap is... Unless you can increase this 75% cap or there was some error/variable in my testing, you are essentially unable to create a build that reliably lands enfeebles. If we also consider how bad the duration and long recasts are on most enfeebles, I would say the enfeeble build got really hosed in XIV so far.
EDIT: From testing magic attack spells, I can say from an anecdotal perspective that the partial resist rate is very very low on Lv1 mobs and the full resist rate on the same mobs is near non-existent. Unsure of why the caps are so different.
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