If you want to sell him on Ready Seal, you can tell him that it will not need to be stripped off the next time you go to reseal the deck. You can give it a light cleaning and reapply. If you tried that with CWF, you'd end up with quite a mess in a few years.
The Ready Seal is penetrating, so it soaks into the wood. When you go to do the deck again, you clean it, reapply, and the RS will soak in some more. You can do this probably two times before the deck will have to be stripped. A huge advantage over CWF and the like.