What is a significant disadvantage associated with the double fisherman knot?

The double fisherman knot is often used for tying together two lengths of rope, particularly in climbing and rescue scenarios. A significant disadvantage of this knot is that it can be quite difficult to untie after it has been loaded. When the knot is subjected to tension, the friction and interlocking nature of the knot can cause it to jam tightly, making it resistant to untie. This characteristic can pose a challenge in rescue scenarios where quick and easy access to equipment is necessary.

While other options address various aspects of knot performance, such as load capacity, slipping, or compactness, they do not accurately highlight the main disadvantage that users experience in practical situations. The difficulty of untying after loading is especially critical for rescuers who need to manage their equipment efficiently under potentially high-stress conditions. Understanding this trait helps rescuers make informed decisions about when and how to use the double fisherman knot appropriately.