once your at that stage of geting this helm you want to drop all your crapy block raitings and go for more dodge/parry... Specialy as pallys since you stock up on block rating to get cheep uncrushable at start of your tanking carrer

Idd prefer 50% miss/dodge/parry and 22% block raiting(+30% holy shiled) as my mitigation stats

Would still keep 50%block(and not any lower) since its nice for threat