Thanks TaylorO! I guess I haven’t been getting it hot enough. The repair I outlined works well, but yours seems far more permanent.
Minimal melt method.
1) Heat a knife blade over a naked flame.
2) Sandwhich the hot knife blade between the two broken leash ends - it helps if someone can hold the knife for you.
3) When the leash ends have sufficient "melt" at their ends slip them off the end of the knife blade together, press together and hold until they have fused.
mitchfromoz - could you send me an email to start some correspondence?
Cheers!