Rotation snap selection

When using "Rotation snap selection", or even "Snap Selection", which are by definition "All Modes" streamline tools, they only act fully/correctly on objects.
If for example, I have a vertex selected on an object, and use "Rotation snap selection" > RMB (to snap selection to location/orientation of target, the vertex does move to location and the manipulators orientation changes to target orientation, but the selected vertex normal does not align to targets orientation.