@LeonL definitely not a stupid question. A variety of things can affect or change the characteristics of a rope and its stretch/rebound amount. Removing outside variables such as water and air temp the focus being on the make up of the rope. Without giving away what we do, things such as how the braid of the rope is laid up, yarn tensile strength, yarn mass, how the yarn was extruded and if the yarn is twisted and how much twist along with gearing and tension on the machines all play a factor in this. For example our competition series and R3 series use different yarns and braids. When working on test ropes we tend to focus on one thing to see how that change affects the rope. Similar to dialing in your ski and messing with the fin or binding placement, just more variables. I hope that helped answer your question.
@Horton loves talking about this stuff with me haha