Thank you for the question. This was a technique I learned as a student at the Oregon Commission for the Blind. When I became an instructor there, I added the cardboard circles to add that level of tactile information. Many of my students who were blind from birth or at a very young age had a significant disadvantage to conceptualize thee concept and the circles really helped. I am not sure how other agencies teach their students/clients - you raise an interesting question. Thank you! Thanks for bringing this to our attention! 🙌
