I used the original (heavy) carabineer on my DN for about 6 months and just some climbing rope and tied knots . I'll admit that I like tying knots. I think knot tying is a great skill that you only keep sharp by practicing.
That being said, I recently swapped out the original carabineer for whoopies and I can't see myself going back. The whoopies are easy to adjust and really knock down my set-up and take-down time. I'll just have to find other ways to practice my knot tying.