I was asked to expand on what happens when the CB and OB are separated.
When the OB is farther down table from the CB it appears smaller (foreshortening) and points of aim Edge, A, B, and C on the OB will be smaller (closer to the CTE line) and the resulting included angles for the same points will also be smaller (degrees) than when the OB is close to the CB.

When the OB is farther down table from the CB it appears smaller (foreshortening) and points of aim Edge, A, B, and C on the OB will be smaller (closer to the CTE line) and the resulting included angles for the same points will also be smaller (degrees) than when the OB is close to the CB.

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