the fillers will keep the cob from breaking, but won't do much to stop grinding. If you're getting broken cobs with kernals on them, then the fillers will help.
I tried filler bars in an M2 about 20 years ago and didnt notice any improvement in corn. I did notice a greater tendency for the cylinder to become unbalanced due to a buildup of dust inside rasp bars and filler plates. I ended up removing the filler bars and hauling them to the scrap dealer so there wouldnt be any temptation to go through the work of installing them again. Tom in MN
The filler bars help with high moisture corn. Several years when we had an early freeze they helped with kernel damage and because the softer cobs bounce in the cylinder and may go through with out being threshed. I am talking about 30 plus % of moisture. Under 28% I did not see any difference We have to do what we have to do. You are right about cylinder vibration. Run it for several minutes and shut down. Also shut down the thresher when you unload to help eliminate this. This allows the dust to settle out.