glass displacement problem

I am having some trouble looking through a window I created with a glass window. The image to the outside it way too far displaced from the original. In this image I hid the wall, showing only the window and the window pane and the grass beyond. The grass as seen through the window is too far distorted. Anyone knows how to correct this in cycles? I am also attaching my node assignment for the glass.

I think I found the answer to my problem. I looked at everything and didnt see any problems but apparently the thickness of the glass was a problem. Adding more thickness through a solidify modifier seemed to work.

Although adding thickness will remove the problem, it will also cause additional rendering complexity for no good reason - flat panes doesn’t cause any refraction, so why use refraction (part of glass shader) at all?

Still using thin glass, you can replace glass with a custom glass setup which uses transparency+glossy shaders instead of refraction+flossy shaders (which is how glass shader is built).

No problems if layer weight/facing is used to mimic the output of a fresnel node.
If using a fresnel node, you have to invert the IOR value for backfacing faces (geometry backfacing chooses between IOR value and 1/IOR value using a color mix, which is then fed into the fresnel node).

Another trick is if you replace the transparency shader with a refraction shader (the IOR trick needs to be used here as well for thin glass), you can still get refraction roughness if you feed it geometry incoming. Mix that up with translucency shader and you have a pretty good semitransparent paper shader.