That may be the case. In my case, if I look at it with the light reflecting off of the nickel, creating sort of a negative, it looks crazy covered with diamonds. It's when I check it at an angle without a glare that I can analyze it. I get it that it is going to be a little uneven, but the part that keeps me concerned is that it is very densly covered at each end and then it seems to get lighter, or the overall diamond size is slightly smaller in the center three or four inches. If it didn't change like this over the long surface of the stone, then the increase in the holes in the center wouldn't bother some much.
The center of mine looks like the second photo on this page while the ends(about an inch on each) look thick like Vasilli's scan. I also have much more of the holes in the center with very few on the ends.