Exactly what I was thinking. We have more than just evasion, so let's see what we can do with the whole toolkit instead of just the hammer.
Of course now I'm thinking of a rogue s&b build taking advantage of all the mitigation bonuses...
Also, the sentinel twist does stack with the same value of an item as it's typed differently (last I checked was before u21, so mandatory grain of salt). That way you could have fire shield, 30% cloak, and the potential of the firestorm greaves for lots of defense in that instance. Having improved evasion, even without actually making the save, equates to a very serious meta game setup.