A full flat ground Delica cuts wonderfully, but would be a lousy Emerson Opener model. Why? Because the FFG blade has too little mass to complete the opening to lockup when waved. I know this because I waved a FFG Endura and really have to draw it fast to get it to wave all the way open. The FFG Delica is smaller and lighter still. Note also that the FFG Delica has a more pronounced distal taper than the saber ground Delica - very little mass as you move away from the pivot.
The folks at Spyderco know what they are doing, and this is why the waved Delica is saber ground.