I'm starting from a fairly clean van normally (garaged at home and work) and still can't get all the dirt off with the BRS. Granted, I'm not scrubbing the van with the sponge, just wiping.
My process is to use a pump sprayer and cover the van in ONR at the recommended mixture, and let that sit for 5 minutes and then rinse with a pressure washer. I then recoat one panel at a time with ONR from the pump sprayer and single bucket wash with the BRS in a bucket of ONR. I then dry with a Minx that I dust with Optimum Detail Spray Gloss Enhancer. My van is polished and coated with Gloss-Coat and I don't see any scratches using this process.
I don't see how the BRS soaked in ONR is any easier on the paint than a drying towel that's wiping up encapsulated dirt on wet panels that have been wiped with the sponge?