STB (which Noman's is too) is able to get everything out. Question is what is more important, whether purity or amount. If purity, Noman's is ok. If you are after amount, I would let soak the bark with 1/3 of suggested water and lye for 24 hours. Then add remaining 2/3 of water and continue. You can swap naphtha for toluene, which extracts wider spectrum and more alkaloids in general. And you can try vigorous mixing rather than slow moves. For many barks there won't be any emulsion if following the 1:1:15 ratio (mhrb:lye:water). For every pull there can be more mixing/settling cycles, I use 3 cycles for first pull 6 for second pull and 10 for third pull.
If you decide for toluene, be aware it needs another technique than freeze-precip to get alkaloids out.
Acceptance of the fact that our reality is not real doesn't in fact mean it is not real. It just leads to better understanding what real means.