I have to admit, you never fail to deliver. Couple of thoughts.

1. The classes that have the hardest time mastering defenses, i.e. those that don't usually tank, are typically the ones that need it least. It will make your life more difficult but it won't shaft you the way it would shaft a warrior.

2. Be creative. I mastered defenses with an elf tranny *as a hero* before the practice changes. It required some funky exploration knowledge, but hey, you do what you gotta do. Sometimes a piece of healing gear is all it takes to put a particular race/class in the position to tank near-indefinitely.

3. With my current character I've noticed that my defenses often improve during PK fights. This suggests a really cheesy path to mastery. There's probably code in place to make this more difficult, but then again there's probably a simple way to circumvent it (*).

(*) I don't know of any off-hand, nor have I tried to find one.