I don't have any fluorocarbon and don't furl leaders but I have designed a fairly simple experiment to answer this question. Take a furled leader and a single strand of fluorocarbon of the same diameter as the finished leader (not the material that the leader is furled from. It's smaller size would invalidate the data.) and tie a small weight to each so they can be hanging down side by side in a large pot of water. If the answer isn't immediately apparent then you can put a waterproof camera in the pot and take photos until you get one where both lines appear to be in focus. It might be interesting to add a monofilament line, too.
No one is making more water. Use what we have wisely.