The lye's purpose is:
- get get pH high enough, for that one needs only a tad of lye;
- to break down the wood/cells, this is the reason more lye (the 1:1 ratio) is used;
- some people use more lye to get a better separation.
You could try and don't discard the bark soup right away, and compare results to see if it matters, and post result here

. If yield is lower, the bark still holds actives, and could be exhausted later with an extra lye effort. Fine powder gives easier it's values than chips of wood.