I was curious on how much there is to play with as far as copper thickness. I plan to lap my CPU when I get it, and of course lap the heatsink since just lapping the processor wouldn't do much.
I think this is not really useful as Ivy Bridge's primary heat problem comes from crappy thermal compound between the cores and the heat spreader.
It is unnecessary in the newer chips the processor should not have any imperfections in the surface when you get it. The manufacturer models the heat sinks to fit the CPU If the CPU is concave/convex then the heatsing is milled to fit the processor . You will see very little difference in temp. In sandy/Ivy bridge CPU's the old CPU's now that was a diffrent story