I've removed this layer and repotted both trees on a piece of colourbond to encourage root flare.
The layer seemed to produce quite a lot of roots in the end and a very large callous had formed.
One side produced more roots than the other so I scrapped the areas of callous I could get to and applied rooting hormone.
I also cut the bottom of the callous flat.
The tree resulting from the layer seems better than the original tree. It had begun some reverse taper and that's one of the reasons I wanted to try layering it in the first place. I'm happy with the result
The layered tree
Original
Cheers!
Ben