Wanted to know if there is a reason why something like Karl Henkel both his "3D Object to Layer" and "Layer to 3D Object" nodes are not included in the stock nodes ?
Using it quite often to bypass some limitations (Use Copy 3D Object with Material with layers), having scene based compositions not having to select different Z-axis to blend nicely etc.
Once "Allow custom node paths" will be implemented it won't be really a problem anymore, but until then, it's sometimes complicated to share compositions with custom nodes.