master at arms increases the damage of abilities that all on the damage they do in one hit, mostly. that is really nothing a templars kit, unless you use force pulse. so you would be save to not put anything into it. pump up thaumaturge though.
Edited by Lightspeedflashb14_ESO on December 28, 2017 3:01PM
It boosts damage of light attacks, Purifying Light, Burning Light passive and the initial hit of Blazing Spear and Vampire's Bane. I believe it also boost the damage of enchants that do damage, such as flame, shock or absorb magicka.