We used to keep our boat on a spring line between the mooring and the boat house. I am under the understanding that that is now illegal. But let me tell you we rented a jet ski and went water sking. I backed up over the line and it got sucked in. It was a royal pain to get freed. 90% of that line I think was around the shaft. That being said I would think it would at the same time cause damage to the trampaline.
