I have a delta and a delta long. Both lines have the same problem. The coating breaks just behind the nail knot or wip finnish (back of loop connector). I have tried different knots and different loops but they soon crack behind the knot. I am affraid that the coating will slide off of the line if I get a big fish on. Has this happened to anyone else? None of my Rio lines are doing it so I don't think that it is something that I do.