Clay bars are used to clean contamination off of the surface of paint. Go to autopia.org and type what you just said. I would never touch the surface of my paint without cleaning contamination off of it. Alcohol is in quick detailers, but this does not get the paint smooth. Yes, a wash and a quick detailer used after gets the paint much cleaner than just a wash. However, if you are going to use a random orbital buffer such as a PC 7424 or a rotary such as a PC 7248 and you do NOT clay bar, you will be rubbing contamination into the paint. THIS causes scratches. You are full on about not using dropped clay bars, but this is why I always tell people to cut the bar into halves, or thirds. If you are going to list information or advice here, back it up.