Max bark and crush ward is putting trolls damage at ~150 on my rogue and skill hits rarely hit over 400. Try that without any buffs and you can compare. Wards aren't lame, there's just usually better skills to use. I run bark touch embrace breath and crush ward and it's really great.
By max I mean 35/30
Ward of Giants is a good buff against Trolls, I cannot disagree, but 40% of others bosses and mobs don't use crush damage. During those fights any points you have in Ward of Giants is a waste. It would be far better to move those points to Sanctuary, Bless or putting in some kind of dps so you can level faster.