Well Dex now increase only dodge and not much really, soo turtle don't need that small dodge increase and maxed because of power increase too.
About that Attack Shackle, yeah and mostly in every party, Turtle and SK is there ....xDDD
Still I don't know is this based on auto attack or even skills too, I can't be sure since I didn't play for long time lol.
Dex never really helped Turtles to begin with. I just like having the passive.
And yeah it's auto-attack. Skills can still get through, but that's where Guard comes in.