This depends how you define Clean. I've recently started to hose down my bowl before a grill session. First get all the ash out with the help of the One-Touch cleaning system; then i use a brush to sweep down all the ash the One-Touch can't get to; Then i flip the grill over and knock out more ash; then i hose down the inside of bowl.
jeeze , I jokingly suggested something similar in another forum and got royally flamed for my trouble. but I hear ya. prob'ly work great.Remember that charcoal igniter fluid that you don't use since you started using a chimney? If you saturate the inside kettle walls from about the food grate down, and stand back to get it lit safely, it does a great job of burning the crud off, and is kind of fun to watch too.