My Tallow soap is more soluble than I expected

I wonder if you could cast your eyes over this recipe for a high Tallow soap for me because it is not behaving as I expected from reading the forum. It seems very much more soluble in my soft water than I had been led to believe.

High Tallow, Dual Lye, Cold Process

Tallow (beef) : 75%
Coconut Oil (76deg) : 15%
Shea Butter : 5%
Castor Oil : 5%
Fragrance : None
Superfat : 2%
Lye : 31% comprising NaOH : 95% / KOH : 5%
EDTA : 0.5% of total batch weight

Cure time : 4 weeks

I made a small batch (300g of oils) and all materials were weighed on a 500g x 0.1g scale with the exact weights below...

Tallow 225g
CO 45g
Shea 15g
Castor 15g
Purified Water 99g
NaOH 41.1g
KOH 3.4g
EDTA 2.3g

Batch weight should have been about 454g and when I took it out of the mold to cut it was 428g. After 4 weeks of curing it was exactly 400g.

Now here is the issue... while the soap is white and hard enough that it is difficult to dent with a fingernail, as expected, as soon as I use the soap in my water (naturally very soft) it makes a very generous lather immediately. I was led to expect a somewhat thin lather which was why it was supposed to need the dual lye to help with solubility.

The bar softens quickly when wet and after only three days of one-person use has shrunk from 100g to just over 90g already. It leaves a slight lotion feel to my hands and needs a lot of rinsing. The bar feels somewhat slick if it is still wet from the previous use and barely needs any water to make more lather.

There is a slight tallow smell (but there was when it was newly made too) but it does not linger on the hands.

Have I been trained by commercial soaps to expect too little from this recipe and perhaps I am being surprised by the generosity of its lather or is there something that you would suggest changing?

I have another small batch of 75% Lard, Dual Lye coming off the shelf in just over a week and wonder how that will behave too.

I've made that exact recipe, only 100% naOH, soft water, and did have thin (like 2% milk) lather with a few larger bubbles. It would be creamier if I started with a recently used non dried bar. This makes me think that the koh is the reason for your result.

Let's see what othershe have to say. For now I've given up on dual lye. I don't like the lather or the softness of the bars.

I'm totally leaning on the KOH. Using that instead of 100% NaOH will always make your bars a little more soluble in water and that goes back to why we use KOH for liquid soap and NaOH for solid soaps. Try the recipe again with 100% NaOH and see for yourself.