Secret #8 stated it is not necessary or even a good idea to make a tight knot when tying a balloon. With a normal knot, you can actually roll the nozzle knot toward the nozzle to lengthen your balloon by an inch – and it is easy to do!
The knot tightens as it moves. You only get to pull the knot once. So, get all the length you need – or can get – the first time.
I use this most commonly when my mermaid tail starts to get a little tight. By rolling the nozzle knot, air filling the new length relieves the stress of the balloon. I avoid a pop.
Another common use is when I teach children to make a one-twist sword. In every class, invariably I’ll have a couple of boys with sword handles too short to grasp. Rolling the nozzle adds length and makes for an amazed and happy sword-owner.