Ha! That video is pretty amazing. I was thinking more in a "sitting down" context when you're using a sax stand. That's also a great way to dent your horns... But still pretty damn cool!
I actually completely agree with your philosophy. However, I actually tried making longer videos at first. Check out my clarinet videos. And then compare the view count to any of my "2 minute" videos. Unfortunately the view count is probably the best tool I have to gauge how well my videos do, and it seems pretty clear what people want. Also it takes so so much more work to create those longer videos. For a fraction of the views, and complete lack of revenue, it's hard to justify spending all that time.
But I really hope things eventually take off. I'd love to go back and start making 10+ minute videos for every instrument.