“…data from the 13 million students who took PISA tests showed that the lowest achieving students worldwide were those who used a memorization strategy – those who thought of math as a set of methods to remember and who approached math by trying to memorize steps. The highest achieving students were those who thought of math as a set of connected, big ideas.”

It really is important that maths teachers stop teaching handle-turning methods and equating speed of solution with ability. See more here.