that doesnt have full CTC tho. You have 67,97 Block meaning you have .97 wasted block chance.
You do not recieve benefit from mastery untill you reach a full percentage of benefit from the mastery rating.
You get one mastery point for each 179,28 worth of mastery rating.
You get 1.5 block and critical block chance per mastery point.
179.28 / 1.5 = 119.52
You do only get benefit from mastery every 119.52 worth of mastery rating (rounding down)
What this means is that if you're sitting on 4299 (as you are in your example), you've wasted 116 mastery rating, which could of gone to other nonwasted stats, like parry. Or you can change one gem from stamina + mastery to pure mastery so that u reach 4319 mastery, which is only 17 rating above the next breakpoint, leaving far less mastery wasted.