although this appears that the usbc is making an effort to join the real world they are still very backward thinking when it comes to approved cleaners for bowling balls. the original idea behind this approved rating system for bowling ball cleaners goes back to when chemicals were used to soften the coverstocks of plastic bowling balls in the late 1960's and early 1970's. softening these ccoverstocks meant more friction was created and this meant more hook. modern bowling balls do not need the application of these chemicals to make them hook more. the coverstocks on todays bowling balls are light years ahead of the plastic coverstocks of that era. soaking a modern bowling ball in those types of chemicals will ruin the ball. therefore there is no advantage for the bowler to soak these balls to try and gain a competitive edge.
however, i see nothing wrong with using these chemicals to properly clean the coverstock of a bowling ball. while there are many bowling ball cleaners available on the market many them them do not remove all the marks, scuffs, grime, etc., that accumulate on the surface of the ball. as i've stated on this website before a bowling ball or an arsenal of bowling balls is a significant investment for many people. it doesn't make sense for someone or some governing body to tell me what i can or can't use to clean this investment.