I too dislike the MIDI cable coiling, but think about this for some perspective.
The problem that you are describing is called "super coiling" in molecular biology (and probably in other fields too). DNA, which behaves very much like a coiled telephone wire and our MIDI cables, intentionally
supercoils about itself many thousand times. DNA packs and unpacks itself with the help of proteins that help it coil and uncoil.
Coiling allows it to pack a ton of genetic information into each of our cells (we are made up of trillions and trillions of cells). Uncoiling allows it to make copies of itself. If DNA did not do this, life as we know it would probably not exist, and thus we could not play our Zendrums.
Since my DNA already does this, then it is good enough for Zendrumming. I just unplug once in a while, uncoil, stretch
, plug in, and play on.