Lets be honest here. The reason people went for mastery is because it smoothed out the damage. Dodge/parry has always been a higher damage reduction but more bursty.
Now lets look at 5.4. Increased rage from the devastate/shield slam crit change along with more revenges (due to more dodge/parry) will mean that damage will not only be less, but it will also be smooth (smooth enough). Parry/dodge will destroy mastery builds next patch, you get so many advantages and I'm really glad it got some love.