I taught an friend to quilt and used pin wheels, never again, did she have a problem with them.........until I used the Jenny Doan method.....after about 10 attempts she finally got it.
Very difficult lady to teach, brilliant mind but found blocks very difficult. I showed her how to fold fabric to strighten the edges and avoid 'bumps in the strips, She could not even cut a square and getting her to cut down oversize blocks was a nightmare.......I got a few more grey hairs teaching that lady.