Yeah ...
I lose around a meter of range if I don't double-wrap .....
But it's not a huge loss, I've got the line from the back of the spear through the muzzle, back to the line clip, back to the muzzle, back to the line clip. So I've still got over 4.5m of 'normal' range, and I've found that the bungee is streamlined enough to make the shock of having to trail it fairly inconsequential.
Why do you think I can't get the line through the muzzle? It's attched to the spear, runs through the muzzle, and then to the fastening point if you're using a normal setup ... same here. It's just not tied to the gun ...
It's a schweet setup, I've gone over to this system about a month after I got the gun. Haven't used anything else except straight spear-line-gun setup on cavegun.