Look, people: I fell for it too. I tried washing my diapers in teensy weensy amounts of very gentle soap.
It. Doesn’t. Make. Sense.
Let’s say, through some unfortunate series of events, there came to be a massive amount of poo and pee on my clothes. Would I wash them in the weakest, tiniest bit of soap possible? Nope: I’d use more soap, and I’d use a strong detergent.
For my comparison above I measured to Line 1 for Tide HE Liquid, which is the same as the max. line of Kirkland Free & Clear. For the “cloth safe” option, I followed the instructions on Omaiki’s laundry soap.