Arcane Subtlety is a Mage talent that grants Dispel resistance while reducing the threat caused by Arcane spells. It is a very useful talent for arcane mages across both PvE and PvP as it offer multiple benefits simultaneously.
Uses[]
Dispel resistance is invaluable in PvP situations, specially for a class as reliant on buffs as the Mage. It can prevent both your buffs and the dots you place from being dispelled, protecting from [Purge], Dispel, [Mass Dispel], [Spellsteal] and others of the sort.
The threat reduction is excellent for mages that use Arcane spells as a primary damage source in raids. 40% threat reduction to Arcane spells is the most that a Mage can obtain through talents, with Frost and Fire talents reducing threat of those schools by only 10%.
This talent is available early in the Arcane tree, and is often taken by Frost or Fire Mages who want some useful early Arcane talents, such as [Arcane Concentration], [Improved Counterspell], or [Presence of Mind]. Since Frost and Fire mages will not be using [Arcane Missiles] as often, this talent is preferred over [Improved Arcane Missiles] in the first tier. The threat reduction is very useful when using [Arcane Explosion] in AoE situations, where a tank needs to hold aggro on multiple mobs.