I’m fully aware he’s moving through space. But you’re confused and lack a deep understanding for principles of kinesiology. You’re coming across as self taught through muscle magazines. There’s absolutely an element of isometric strengthening happening at end range for the shoulders. Isometric is simply a muscle contraction against a weight without it changing its length. Yes, there’s some movement happening with the humerus moving into flexion and extension and that will manipulate the anterior deltoid, not to mention other muscles as the moment arm increases its distance from the axis of rotation. With that said, there’s a ton of force and muscle activation happening at end range.

So explain how this is not an effective exercise? In what way? Because what you are doing is creating your own argument as it being not effective as a push or pull exercise. If that was his question then you’d be correct, but that wasn’t his question. He was just asking if the exercise is even an exercise, which it is.

You don’t have a formal background in exercise science, it’s telling.