I understand what you are saying. But, I have 38 years of working on RV's INCLUDING thousands of dump valves. There is NO flaw as you describe. IF debris is getting where you state, then either the valve or the seals are not to spec. Now, the Valve makers are insistent that the valves be installed either 90 degrees to the ground(95 percent are)or upward or the handle at 12 o clock which is ideal but almost impossible on the majority of installs. Any deviation down from the 90 degree can allow debris to flow into the valve body cavity at the handle end. But your complaint, I doubt I have ever seen it. Usually as I stated the paper/debris is jammed into the end cavity by the blade. Doug