Not being a benchstone whiz (to my detriment), I can only assume a DC4 is a benchstone.... probably diamond.
Is there the possibility that, since wet/dry around a stone is going to have some looseness, and therefore some "give" to it, you're putting a slight convex edge on your SCZ? Then, when you return to the bare stone, as you place the scandi-grind down on the stone, it is rolling forward on that convex surface and creating a micro-bevel?
Just a thought.......
Additionally, I know that ALL of my scandi-ground knives (Moras, Helles, and EnZos) have some convexity to them straight from the factory. Oh, they're NOT convex ground, mind you, but they do have a very slight belly to them. When I grind them, flat on the bevel on my waterstones, with as much precision and care as I can muster, I can tell by the grind marks that they are convex. Only one or two of my scandi-ground knives have only recently been honed enough to where they are truly flat, and therefore are ground "to zero". Then....... I put the slightest of micro (nano micro if that is possible) bevels on them by 4 or 5 very light strokes on my fine, white sharpmaker stones.