You don't have any way of knowing the zone kept us in the game. The only time they kept it close in the first half then got the lead in the second half was off banging open threes after we inevitably collapsed on a guy who clearly didn't want to shoot a mid-range jump shot or a midget guard started driving with no intentions of trying to attack our 7'2 Center.
I think our zone could be filthy if the guards paid no mind to a guard getting past them or a 3/4/5 catching a pass at the high post. Obviously deny, but if they get the ball there, force them to make a quick decision. You can't just hang out there offensively and players aren't used to A) Having the ball there and B) Shooting from there. Also C) It's tough to grab momentum off a couple 2 point jump shots.
With our length, if we geared the zone to stop modern day AAU emphasis (Dunks/3 pointers) and encouraged awkward 2 point jumpers, we could have a top ranked defense every year, in every category. This is one of our best defensive teams yet we still allow a ton of open threes and players to duck behind the Center.
Pace of play also greatly factors into our defensive efficiency ratings. PPG are low, limited possessions and teams get antsy. Remember us vs Butler in 2010? We're like 10x worse than that. Every time down the court you can go to the bathroom, microwave some food and let the dog out before we take a shot.