So for you the warlock is in the same category of dmg per second class as guardian, templar or dhan?
I will try to explain to you. If you don't understand I will explain again, and again...
Guardian is str... usually. Str gives defense. So when you buf put a point to str, buf your defense is also increasing. It is ok so far?
Guardian have protection which for a +9 glacial it is giving a lot of defense.
Templar have mb, which interestingly is not 40 sec like is the warlock shield...
Now warlock is int build and int don't give pdef gives only a bit of mdef. Don't have any protection to increase the armour defense, no skill to transform his int in pdef, only a shield that now is 40 sec.
PS: Play the client not on forum...