-- The problems with seed spacing on that drill are due to the fluted feed.  Actually, the longer the seed rattles around in the tubes, the more chance of smoothing out some of the clumpiness that results from the fluted feed. 

Air drills have the seed in the lines for a much greater distance than the box (gravity-fed) drills, but seed spacing can be pretty darned good with an air drill if it is well-designed.  E.g., the Flexi-coil carts deliver very nice randomized spacing.  It's definitely not singulated like a planter, but at least it isn't clumpy like the box drills.