Whatever soap you start with, Not Ally, is what you end up with after salting out. Just minus the fragrance, color, and other additives.
If you don't use any lye in the salting-out process, the soap still contains all its superfat. If you do use some lye, you can easily reduce or eliminate the superfat. The salted-out soap won't be lye heavy if you do add lye, because the salting-out step removes water-soluble materials and lye is water soluble.
Salting out doesn't change the essential character of the soap, so judge a salted-out soap in terms of the original recipe(s). If the soap scraps are from bath bar recipes, then you end up with bath bar soap. If you want a 100% coconut soap for the laundry, then you'll want that regardless of whether it's salted-out or freshly made.
In Boyago's case, he used his salted-out soap (scraps from a wide variety of recipes) for laundry soap but he clearly knew it wasn't going to be as strong a cleaner as a 100% coconut soap. But to get some good use out of soap that would otherwise be useless -- that was his motivation.
In my case, I'm using my salted-out soap as bath and hand soap. I chose to add NaOH to reduce but not eliminate the superfat. It is a mild soap that lathers well for bathing and hand washing. Yes, it doesn't have any glycerin in it and the superfat is low, but the soap is still good soap. I like how the salting-out removes the color and fragrance, so I can color and scent the soap as if it's freshly made stuff.
" How do those compare w/regular, ie; store bought powders in terms of cleaning? "
Do you mean how does a high or 100% coconut soap compare with store bought detergents? Plain soap doesn't contain optical brighteners, so it doesn't make glowingly-white whites. Plain soap also doesn't contain enzymes, so it may not be as good at removing some stains without extra pretreatment.
I have been making a 30% lard, 70% CO soap with EDTA for my laundry soap. The amount of EDTA is still a work in progress, but I'm using a fair bit more than the 0.5% I'd normally use for bath soap. My last recipe for laundry powder was this:
80 oz (2270 g) grated soap with high percentage of coconut oil
80 oz (2270 g) washing soda (about 1 1/2 boxes)
80 oz (2270 g) oxiclean-type oxygen bleach powder
Use 2 TBL to 4 TBL per load depending on size and dirtiness. I'm definitely seeing better results in terms of cleaning and whitening with this blend than the usual recipe that calls for baking soda + washing soda + borax + soap.
I just don't think the baking soda adds anything to the party, so I eliminated that totally. I also think washing soda and borax occupy the same niche in terms of adding detergency to the blend. Washing soda gets my nod as being more effective than borax in a dry blend, so that's why I'm using it over borax in this recipe. If I made a liquid clothes washing soap, I'd use borax, because it will remain effective in a water based product unlike washing soda.
I also think I simply need more soap per load for better removal of greasy dirt and skin oils, so I'm using 2-4 TBL of the blend. IMO, the ladies who are using 1-2 TBL of the usual mix to clean a load of laundry are definitely not dealing with greasy, muddy, stinky chore clothes.
The mix seems to be working well for me -- my HE washer isn't getting stinky every month or two like it does with commercial detergent and I'm not seeing excessive foaming or scum buildup, colors are remaining clear and bright, whites are acceptably white, and my clothes smell good.