Good reply mate. My answer in this thread was to the individual poster. He said he was new to this style of fishing (chod/helicopter) so the safest way in my opinion for him was no leader. Imagine if he was advised to use a leader and then went on to thie it on with a swivel and proceeded to snap off? I agree with you that having a tough leader on when fishing a rotary arrangement would stop the swivel having any chance of damaging the line. That is why, when fishing without a leader (which I do most of the time, not always but most) I, at the time, adapted the use of a lead insert as shown in the last picture. Manufactures have now added bits to there range so that I don't have to anymore. The fox ones are perfect and nice and neat.