discrepancy is 80-147 for contested vs. 62-148 for uncontested
I'm to lazy to do the math now, but my gut tells me, you're still not having a significant sample size .
By the way, I got some very good results employing the 2-3-zone recently. I won the championship and my first two BBB matches using it:
(62459781)(62459783)(65259349)(65259451)Though to be fair, i didn't win by stopping the inside attack, but by dominating the boards.