i've noticed the same thing with warden gear. got chest peice to 8 or 9 and going off what it shows in the image i should be around 55-60% tankier then base gear. the bar is getting pretty close to the end. yet still dead by 3 heavy attacks
The last test we did, the defense actually worked. And I noticed it working on some other characters. I'm not sure what's causing the bug. Everything else works fine though. I've tested this on 3 different armor pieces lol.