discalculia

"Dyscalculia or math disability is a specific learning disability involving innate difficulty in learning or comprehending mathematics. It is akin to dyslexia and includes difficulty in understanding numbers, learning how to manipulate numbers, learning math facts, and a number of other related symptoms."

wikipedia
This business of what is a simple block keeps nagging away at me. Quilting is so much more than sewing. As someone who struggles with maths even simple patterns can be taxing at times. There is also less pattern to hide any mistakes in and so missed points stand out far more than usual.

Simplicity can be taxing.