Deviation Checking and Deviation Gauge

To my knowledge, Deviation Checking seems to be a simplified version of Deviation Gauge.

 

Deviation Gauge has "Measurement Definition" allowing specify how the measure the deviation between two objects. The only Measurement Definition method that I can't understand is 3D, for which the official documentation explains: Computes the deviation in 3D space, as for example from a selected object towards a reference object.

 

Deviation Checking does not have "Measurement Definition", therefore I can only guess how it measures deviation.

 

 

1. If the objects to be compared are two curves, two edges or two surfaces, my guess is that, both Deviation Checking and Deviation Gauge (Measurement Definition=3D) would compare two points having equal parameters. 

 

2. If the objects to be compared are a curve and a surface, my guess is that, both Deviation Checking and Deviation Gauge (Measurement Definition=3D) would compare a point on the curve and its projection (normal) point on the surface.

 

Thanks!