IAD has the black diamond setup really well because
1)its far away from the other lanes, keeping the kettles away
2)they don't even advertise it as security, just the "dulles diamond" signs, further keeping the kettles away

I was there on a busy Saturday in the summer, the folks upstairs were trying to send us downstairs to it but there weren't many folks ahead of us (especially in the non-elite que) and I had no desire to join the masses down there in the small screening area. Got through the main one in 5 minutes.