dex and accuracy

hi. i have farm golden skeleton for a few days and one day i party up with a fellow brawler. He surprised that i can tumble the GS a lot. Is this because i have put 3 stat point to dex (which i think is very little to me to get the effect of accuracy) or it all just about luck. but it really frustrating because i can hit the lvl 60 mob (not sure the name is) really well. and i think the dodge rate of GS is really high.

 

I have put 50 points to dex. And i can hit with a better accuracy when fighting forestia. I will try fighting GS later. But my dmg become lower and less hit per swing. This is because less agi, less dmg, lower aspd.

 

Curious about MD brawler. How much would Dex help/hurt?