I've been making a version of this for a long time, now. You are right. It works well.
As a carpenter I am expected to have learned my trade before working on someone's house, yet doctors get to practice. If you meet a doctor and as what they do for a living they will reply that they practice medicine. Isn't that a scary concept?
Mema, glad to have you back and hope your health issues straighten out for you soon.
When I was in Kentucky I stayed with some very good friends of Granny's. She gave me a recipe for making a laundry detergent that she claims cleans better than anything commercially available and only costs about a penny per load. I recently make a batch and Hope tried it on some extremely greasy and oil clothes of hers and some of her sons clothes that she hadn't been able to get the grease stains out before. Much to our surprise everything came out spot less.
Laundry soap recipe
1 bar Fels Naptha soap
1 cup Super Washing Soda
1/2 cup Borax
4 cups of water.
Grate Fels Naptha into a large stock pot with water and simmer until melted. Add 1 gallon hot water, powders, and stir until dissolved. Pour into 5 gallon pail and add hot water to fill. Allow to stand overnight.
Use 1/8 cup for front load washers and 1/4 for top load.