Dual Blade Builds

I think I know the point of advanced dark sight now. Looking at this video: http://www.youtube.com/watch?v=I5j0ZpoDn8w it seems to remove the delay from chains of hell. Apparently, the chains of hell delay makes it so you can't go into dark sight in that delay, so staying in dark sight skips this, letting you use chains immediately again. However, the first chain and the attack itself seem to be counted as separate attacks, so there's still only a 24.5% probability of this happening. This somewhat eliminates the problem of dying in dark sight because chains (both failed and successful) gives you such long invincibility that you could keep using chains even with near-death hp until it forces you to leave dark sight on its own. I think it's better to max it in this case, but the skill is still kind of a double-edged sword. Hopefully this can be figured out before people reach 4th job because it's passive and would need a ton of nx to reset.