It's more accurate than bracket by far; I've seen people succeed or fail simply by what side of the bracket they are.
The top two seeds still need to play each other to advance and, should other players step it up, the match could actually determine who advances. Seed is important to make sure you get out as the pools get harder, but for the 2nd to last pool you'd just need to make sure you advance.
Pools can bring about issues when it comes to "Oh, I have a guaranteed advance. LOL TIME" where someone 2-0's everyone then goes Ike for kicks and loses 0-2 to someone else, which in turn puts him above the others. That does suck. People should still get more matches on average though.