"[dev1027] [dev1032] Status Allocation System + Damage Calculation Broken/Unbalanced"

Check this out for thm nuking stats/testing/calculations

Link 1: more of rank topic showing how rank difference and int difference are the main concerns with defense/dmg.
http://forum.square-enix.com/ffxiv/threads/6355-dev1027-dev1032-Status-Allocation-System-Damage-Calculation-Broken-Unbalanced

All tests showed consistently that the R59 mob defensive abilities increased 20% from 58 to 59 while from 55 to 58 each step is only 3%. This proves the calculation system was unbalanced due to player and mob rank. This may be because the R59 mobs' innate stats were raised inconsistently.

Ice, earth, and water are considered umbral elements, while fire, wind, and water are considered astral elements. It's just like monster families; there are different monsters that are all arcana (bombs, dolls, evil weapons, etc.), just as there are different elements that belong to the same pole (fire is astral, etc.). If you lower resistance to one element, it's either an astral or umbral element, making astral or umbral spells do that much more (i.e., using Burn then Banish).

Link 2: topic on forums discussing the importance of elemental alignments taking priority over int/piety
http://forum.square-enix.com/ffxiv/threads/5851-dev1032-All-THM-Spells-Completely-Int-Blind-As-Intended

The fact of the matter is too many people put merit in int, pie, and mnd, when you should be worried about your elemental stats. Earth, ice, and water are umbral stats, 80% of THM spells are umbral. Fire,Lighting and Wind are astral stats, less useful since only 20% of THM spells are astral.

Int and pie do make a difference, but if you honestly don't see an effect when playing around with those, you should try restatting your elements.