From Worms Knowledge Base
When using the Ninja Rope, selecting the Harness allows you to pick up a worm on the same team and drop him off at any location. What's more, it doesn't use up your turn.
'Picking up' another worm is not heard of in Worms so this might require special programming. It would certainly make for a difficult animation.
This would certainly be useful if you did not have select worm and another worm was in danger of, say, an easy water kill or rising water. It would also generally be useful for moving worms to a location from which they can fire better, or access more areas when it's their turn. This tool would not fit well into Worms as it removes some of the basic strategy involved in the game, namely the strategy of anticipating the future of the game and leaving your worms in a safe place to compensate. Allowing your worms to be moved to a safer location with such ease takes away that important part of gameplay. One could argue that Select Worm does a similar thing, but at least movement is limited as usual with each worm selected.