Mizuno recommends starting rough and working with successive finer grits, as is the norm with a flatting/smoothing process. Also, as I recall, Mizuno a) never uses anything a rough as 100 grit , and b) starts at around 400 and works to around 1500 grit. This would give a much smoother finish. I also suspect this will get rid of a lot of the rough edges which will alter the nature of the Pd deposition. I have a deal of experience of this process over the years, and when you start rough, it produces the rough edges you have. But as you go smoother, it produces an increasingly well defined, burrless, clean edge
In my initial test on the mesh sample, I followed Mizuno's sequence of increasingly finer sanding grit. Evidence from the subsequent burnishing showed that the sharp burrs did not disappear with 1500 grit. It looked like the finer grit only resulted in a sharper edge on the burr. I suspect that at micron scale the Ni is sufficiently ductile that the material displaced by the sanding is not entirely removed, and is partially smeared over the edge of the land resulting in the observed burr. A further look at the sanded but unburnished material is possible.
This leads to the second point which is that you point out that the most Pd is deposited on the rough 100 grit mesh. Have you measured the actual weight gain of Pd on the mesh, and is it sufficiently well defined, area and consistency of treatment wise, to be able to calculate the equivalent weight that would be deposited on mesh of area Mizuno used. If so, does this match the ~ 50mg that TM recommends?
With the latest test I was not attempting to precisely quantify the deposition of Pd, but rather to explore the parameter space of burnishing on Ni foil or plate, as suggested by Ed. Whether the apparent increased deposition rate with coarser sanding would be beneficial to LENR activation of the material is unknown. At least it is now a somewhat controllable parameter. Further testing will certainly be done, but not until after ICCF.