Can you reduce detail with a normal/bump map? The usual workflow is to take a high detail model, such as a sculpt, create a lower detail copy, then bake a normal map off the high detail to use on the low. Is it viable to do the reverse?

I need to keep the overall geometry of my model intact for various reasons, but I would actually like to eliminate certain surface details with a texture within some parts of my material setup, while having the rest of the geometry intact for other parts.

Note that I don't necessarily mean a lower detail model in terms of vertex count, but rather in visible details. For example, here are two UV spheres. One has been crumpled. If I rendered it, it would have complex shading due to being crumpled, and the wireframe sphere would have smooth shading.



I want to give the crumpled sphere the smooth shading of the non-crumpled sphere, but keep it's geometry complex. This would cause it's silhouette to still have the high detail of the crumpled sphere.

Can this be done?
In the case of a spherical object, it is pretty simple. Just add a Normal Edit modifier and enable Auto Smooth in the Normals panel of the Object Data menu. 





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