Applying DoTs and Accuracy and skill speed question

I would like to know what causes bosses to resist the DoTs when I am trying to refresh them(such as windbite and venomous bite). It is really annoying because of the 2.5 second cooldown. Does it mean i need more accuracy or how do I prevent that from happening.

Then, I realized that skill speed affects NOTHING that the bard does... and it is everywhere on all our gear . What's the point of it.

The last one is accuracy because none of my attacks seems to miss except of the DoTs wich says "Failed to Apply" when it "misses"(I don't even know if it is due to it missing or just the bosses resisting the DoT.

I would really appreciate getting an answer to those question. Thx :)

Skill Speed decrease GCD. (You need a very high amount)
Accuracy cap near 390 at 50 (unless mob level increase in higher tier)

400 = .03 ? thats so bad i don'T even want to talk about it... and it does't affect everything.( like buffs)