Suppose it may kind of be necessary for Guardian mastery to not affect physical DoT effects, and it's been a weakness we've had for a while anyways. It may be a slightly rude awakening for new bears going into Highmaul that aren't expecting their fancy mastery to not work against certain physical mechanics.
Still, with the RPS going into progression (stat balance aside), Guardians don't really feel like active mitigation tanks versus passive ones after all these beta builds. Don't get me wrong, the package still works enough to keep us balanced with other tanks, just feels off that 60-70% of my self-healing via actual heals/absorbs would occur if I just sat there doing nothing, even more if we just did a DPS rotation that incidentally included T&C. Doing some test runs with a Blood DK had our self-healing/absorbs and damage taken about the same, the only difference is that most of my self-healing didn't require me to push any button. May just be semantics at this point, since using our AM is definitely still worth using despite the massive amount of passive survival going on in the background.