Game Mechanics: Healing / Buffs - No Faction Hits

[nall]

While Faction grinding In Kael Arena on my Cleric, I've noticed that regardless of number of heals or buffs to anyone fighting mobs, zero faction hits occur.

Instead, healers must Melee, Nuke or root in order to gain a single faction hit.
Ive also noticed this is true for boss mobs such as Vindi etc. Makes it rather Difficult to faction as a pure healer...