Water material seen from underwater

Questions
1

Has anyone made a water material that works if seen from below, not only above water?

All demos of WaterMaterial and Ocean seem to work properly only if camera is above water, never underwater. From the shader code it seems that this is to be expected and that the up vector is hardcoded on the shader.

2

You are right. The water material is expected to be seen from the top (mostly because of the ref/refraction texture reads)