In variogram modeling with multiple variables and anisotropy, if all the variograms cannot be modeled well, it is critical to model the cross variograms well while the other models can be sacrificed somewhat?

The statement is false.

Step-by-step explanation:

If the modeling is with multiple variables it is necessary for all the variables to be modeled well such that the criticality of the model is dependent on all the variograms. It is not dependent on the cross variograms only.

ok then what happened.

1/3 + 1/3 ≠ 2/6 because 1/3 alone = 2/6  

step by step explanation:

1/3 + 1/3 = 2/3       2/3=4/6