I feel like the true strength of the talents deep in the Templar tree are mostly undiscovered and untapped due to one primary reason:
Current max-level content is trivial to the point where a pure tank is not at all required. This will most likely be fixed with future content updates, which hopefully will increase the difficulty of later dungeons. Currently, though, hybrid tanks, which offer more utility than pure tanks, and often contribute similar or more DPS, are preferable because most monster encounters at this level simply do not require some of the heavier defensive talent investment in the Templar tree.
This isn't entirely a bad thing, as it promotes build diversity and player creativity. We've already seen some very creative 'tank' builds come from players in recent weeks.
That said, on closer inspection, the deep Templar tree offers more than just defense, and players wishing to try a more DPS-oriented Templar build have some very interesting options, especially looking forward to the 45 and 50 updates(simply due to having enough talent points to invest in all the cool Templar talents). Note that while Templars do have access to multiple Taunt effects, threat generation is still tied to DPS, so players having trouble holding aggro especially in AoE situations might want to consider a more offense-oriented build rather than going for pure mitigation.
More 'extreme' tank encounters, such as Avatar of Amun, will likely still require pure tanks.

