> Quote -   So if I am correct (which I doubt) there are cases where either Bump normal or displacements are useful but Bump wins over normal Although  I must admit I was taken by the renders blackhearted  posted where the displacement in my tired old eyes just had the edge?  But that was displacement over normal and not bump !

the disadvantage of normal maps is that they dont actually displace the geometry -- so normal mapped wrinkles and seams will look like displacement mapped ones from dead-on, but the silhouette of the figure/object will remain unchanged.

for example in the attached image the ridges along the front and back of the grip are done with a displacement map. you couldnt do this with a normal map because despite the ridges appearing when viewed directly, when turned to the side like this the silhouette of the grip would remain perfectly smooth. think of normal maps like bodypainting:  i can paint the appearance of a pair of jeans and a tank top on a woman, along with proper shading and shadows, but her silhouette is still going to be that of a naked woman.

the advantage of normal maps is that they render faster, they are visible in real-time in the poser viewport, and applying them is painless:  you plug in a tangent space normal map and set it to 1.0 strength and it looks exactly like it should in Poser. no math node BS, no fiddling with displacement strength values, no worrying if the end user has 'use displacement maps' checked or has messed with his min disp bounds settings, etc.

except in cases where you need to displace the silhouette of an object - such as on my USP Match - IMHO normal maps are usually the better option.

another advantage of normals that people may miss is this:
when you create an object - for example a t-shirt - and release it with a complex shader with displacement/bump/etc, often add-on texturers and tweakers will want to modify the shader for use with their own textures. for example if they want to release a texture set with some raised lettering, ribbing or fuzzy stuff. they can change, screw up or discard your displacement maps, bump maps, etc and the shirt will lose your wrinkle/stitching/seam detail. 
with a normal map plugged into the gradient bump channel, they are free to add/remove bump maps and displacement maps yet the detail from your normal map will remain unaffected.  IMO this is a cleaner way of doing things.