Cutout shader acting strange when viewed from sharp angles

I a was playing around with cutout shaders when I discovered that when viewed either head on or nearly head the clipped pixels become visible again. Is there a way to avoid this?



Any advice would be appreciated.

 

Is this a custom shader, or a built in one? If it's a custom shader can we see the code? If it's a built in one which one? What kind data is being used to do the clipping?