Previous to this study, many believed that it was the friction between two ropes bent together that prevented slip, but this new research discovered the key feature of a great knot is twist within the core. Twist is also a reason why some knots capsize and fall apart.
They also found that a knot can be made stronger if it has more “circulations,” which they define as a region in a knot where two parallel strands loop against each other in opposite directions, like a circular flow.
By taking into account these simple counting rules, the team was able to explain why a reef knot, for instance, is stronger than a granny knot. While the two are almost identical, the reef knot has a higher number of twist fluctuations, making it a more stable configuration.