Is TBN a bad skill?

[Nedkel]

The thing about that is... in most cases IT DOES NOT save a GCD from a healer. And that in probably more than 90% of this (end) game's content. Maybe an oGCD, but then its a wasted resource anyway. (WHM might be an exception bc of their lily/heavy GCD healing design)
Even if it does save your healer a GCD compared to... let's say GNB: GNB DPS is no doubt higher than DRK, but it's a safe investment into dps. TBN is not, quite the opposite. As I said above, TBN saving a GCD heal is already unlikely. Using it only when you know it will break, is indeed "DPS neutral" at best. You can experiment in duty fights to optimize TBN uptime, and still make sure it breaks. That still doesn't guarantee it will bring your healers more dps. This is a gamble with high risk/effort, low reward.
The only (not even a) handful duties -where TBN shines- are Ultimates. Ultimate AAs, raid wide etc. deal so much damage that the shield breaking during its duration is 99% guarateed. So much, I would even say it's overpowered.

This is false.

TBN makes DRK the easiest job to heal and it saves a ton of GCD when DRK uses it consistently.
Maybe not in raids, but in dungeons where the damage is way higher on trash mobs, it does make a difference.