I did this a couple years ago and determined it wasn't worth the time/effort.
Sticky residue from the green leaf builds up on the brush, hardens, and bruises the leaf while brushing. This leaves marks on the leaf. The 'damaged' cells of the lamina do not cure properly, actually they will rot.
Also, learned that 90% of the dirt, debris, whatever crap, will fall off the leaf as it just hangs, cures, dries. Whatever is left on the leaf can be brushed off much easier, after it is cured, without damaging the leaf.