Simply the comment was wrong . Why do you continually bring up "angles and alignments " they were never used or needed to prove that the comment was wrong , they are the stuff of equidistance between sites and Thom .
A hill figure is a picture. When I go to the cinema, the best place to see the screen properly is not the seats right under the screen. When I watch TV, I wouldn't sit on top of the box to look at it from above. When I go to an art gallery, I don't peer round the side of the frame. In all these instances, to view the image I look at it from a distance away, face on.
To view the horse in this way, you will be looking at it from the northwest, as you do from the train. From there, the sunset is on your right and if you on y he train, you are heading towards it. The horse appears to do the same, irrespective of whether it actually does when measured with a compass or viewed from the horse's back or wherever. This is my opinion of the position an artist would intend their picure to be viewed from. You can disagree with that, it's fine. But both you and ED told me I was wrong and that what I was saying couldn't possibly make sense.
I have finished with this discussion, it now just feels like you want to keep arguing the toss over the same points until everyone agrees with you or stops. I'm stopping.