Blood Weapon / other DRK suggestions:

[Granyala]

DA defensive cooldowns aren't things you just use because it's a cooldown and you want mitigation. You're supposed to time those properly so that they DON'T become a drain on your mana.

Mitigation is mitigation and as a tank my job is to mitigate as much damage as possible.
I see nothing wrong with using them on CD (the blue one at least) unless you know sth is going to happen later where you need it.

Though usually I am mana starved because I have to spam the TP combo since, as a hobbytank with rather crappy gear, the osmosis combo doesn't generate enough threat against well geared DPS and Dark side slowly drains my mana.