Im no mechanic Dilwad but going on the box smoker ive got this idea, "could be practical"
and not effect element.If you were able to put a sheet of thin metal 1-2cm above the element that covers the majority of the oven. Place shavings on thin metal piece slide in and element should get hot enough to start heating metal piece which start burning saw dust.
I wouldn't weld this piece in as the ability slide in and out will be easier for you to clean.
Metal piece needs to either act like a shelf (think of a book shelf) and sit on shelf holder thingies or you can bend sides of metal 2cm down so they sit on the bent edges. I would still place a tin foil strip on top of metal piece then add shavings. Once finished slide out metal tray and wrap up burnt shavings in foil and bin. Metal piece stays clean and protects element.
Geoff