I'm not really sure what this proves? That chart doesn't even say what the emergence was in the first place, so a 40% reduction on a 50% emergence rate is much different than a 50% reduction on 85%. Those all done in the same field? What soil type?
I've used a paralink, Flexi-coil 5000, BG5710, BG 8800 and most recently a CNH disc drill. In my clay-loam soils the only one that I would trust over 5mph is the disc drill and it does a better job at every speed including the slow ones. It pulls easier and floats better in muddy conditions. It just requires more maintenance.
AN ERROR DOESN"T BECOME A MISTAKE UNTIL YOU REFUSE TO CORRECT IT
Orlando A. Battista