Didn’t work for me at all just covering the seam (shadowed places too). Waaay too many other things going on including the sky, ground, and other shadowed areas on the objects to still throw off the eye.
To work for me, I had to block the top and bottom and sides of each square. Making two "V"s with my fingers, perpendicular to each other, did it. The two flat sections that peek out do indeed look the same color then.
