Well, at 1/800sec and a perfectly frozen jumping horse I do not think that what we see is motion blur from leafs, especially since the doubleness of it is especially visible in the logs themselves.
On closer inspection I see it actually is CA that gives that double image feel to the crop. I do not know if the CA has been partially processed away, but look at the vertical lighter plank on the right, for instance. on the top of the crop its side has a certain thickness, and a slight red tint to the left most edge of it. The moment it crosses the lighter trunk, the thickness of the plank almost seems to half, and the red edge is gone.
Below the metal wheel, the edge of the plank has a very red tint to it.
Now look the right of other dark parts, like the vertical metal bar... again a distinct red CA line. On lighter elements you seem to see green bleeding in to the left, like with the highlights in the leafs in the background. So my educated guess is that it was some quite strong CA after all.
This still leaves the flat feel of things, which seem to suggest some noise reduction algorythm.
The flatness of the leafs, metal parts and all could be called noise artifacts... They are not noise, but artifacts from de-noise-ing... just like sharpening artifacts are not sharpness but for instance strange light/dark halos around contrasting objects
*edit* : Sorry about picking it apart, haha! I totally missed the part where you explained the CA nightmare. I can understand why you are happy with the shot.