Jon,
No offense intended as this is not an easy subject but...
That's ridiculous. The balls are static & the centers are positioned. There is only one line from the center of one ball to the 'edge' of one side of the other ball. You either look down that line or you look at it from the side. Since the vision center is higher you actually look at it on the vertical plane of that line or you look at it from askew to that line.
If one moves off of the vertical plane of that line a new sight line is established but it is no longer on the CTE line. If one moves far enough one could establish a new line of center cue ball to the center or edge of the ghost ball or nearly any part of the ghost ball. If one moves in the other direction that new sight line would to the OB from the 'edge' inward toward center until it cross over to the other side of the ball.
How many times has it been said that the edge to x line fixes one in the only position to see both lines simultaneously?
The only way one can move & see a different CTE line would be to also see a new & different ETX line & that is only possible if X, the A, B, & C are not points or lines but instead are a group of multiple points or lines.
If that is the case then they must be selected subjectively as to which one to use.
Again, no offense intended with the ridiculous comment. But it seems that every advocate only repeats what they have been told & what they think that they are doing but with no real critical thinking as to what is actually possible & what is impossible.
Best,
Rick