The myth is that any chains stretch at all. They get longer due to wear of the pins and the holes in the inner plates in which the pins rotate.
i have put two chains end to end (both the same make model etc. one old, one new and with counted links) and pushed the links together, it was well still over a link longer.
i have put two chains end to end (both the same make model etc. one old, one new and with counted links) and pushed the links together, it was well still over a link longer.