From reading and rereading these two talents Parry seems way more power fuller than Avoid Blow and as and added befit of reposting damage back at the attacker.
Avoid Blow: Rank + Dex against Attackers Attack Test
Parry: Rank + Dex + Item Size against Attackers Attack Test
This makes Parry better as you get extra steps to your roll, or even if its a size added to the roll, its still at an advantage.
So why have Avoid Blow when you can have Parry?
![Confused :?](./images/smilies/icon_e_confused.gif)