Which knot maintains all of the rope strength without any tension applied?

The tensionless hitch is designed to maintain significant rope strength even when there is no load applied. This particular knot functions by creating a secure point of attachment that distributes weight evenly and minimizes stress on the rope, preserving its overall strength. Because the tensionless hitch does not constrict the rope itself, it allows for a full strength retention of the rope under non-tension conditions.

The figure eight knot, while strong and commonly used, does not maintain the rope's full strength without tension. It creates a secure and reliable knot but relies on the application of force to maintain its integrity. Similarly, the bowline provides a fixed loop at the end of the rope and can slip under no tension, which also limits the strength retention without load.

The clove hitch is useful for securing a rope to a pole or post but does not possess the attribute of preserving rope strength without tension, as it can slide or come undone without weight applied to it. Thus, the tensionless hitch stands out as the option that maintains the rope's strength effectively when it is not bearing any load.