Tank Firebrand can be seen as a variant of Heal Firebrand which focuses more on self-sustain and tanking capabilities by swapping the Virtues traitline with Valor. Other than tanking the build can provide permanent Quickness, Swiftness, high uptime on Fury, and <25 stacks of Might to the party. It has access to lots of Stability and Aegis.
The trait Altruistic Healing will heal the player for a small amount every time a boon is given to an ally. While this may not seem like much, this trait is not subject to an internal cooldown and when the boon output is scaled to 5 players it quickly becomes a powerful way of self-sustaining. Always try to make sure you are in the range of your allies to be able to provide boons to them through symbols, mantras, and other skills such as Shield of Judgment and "Advance!".