Layer Weight vs Geometry Node setup When studying set-ups for cycles materials I encounter a frequent use of Layer Weight node and also the use of the Geometry Node. As I have difficulty to understand those set-ups I have made two very simple setups for this post.

First the Layer Weight node set-up ...

And this is the result 


Then a set-up with Geometry Node ...

With this result ...


Although I can see some differences I don't understand why artists sometimes seem to use layer weight and sometimes the Geometry set-up. What is the essential difference in the two set-ups ?
In your example the difference between the two is caused by the multiply node. If you use an invert node instead, they are identical:



I don't think there's really any reason to use one over the other, but of course with the layer weight node it takes less time to set up.