Duplex......same as LRMP , even betterPossibly, but I doubt it would work, at least not reliably. It is not just the firing pin strike that sets off the primer. It is the combination of the strike driving the primer compound into the anvil. With the primer sitting "Suspended " in the cup there would be nothing for the anvil to sit on. The Firing pin strike would just "Seat" the primer the rest of the way in the cup. I helped trouble shoot a new reloader having an issue like this several years ago. Boiled down to some bad brass and pockets cut way too deep, so took 2 strikes to set off the primer.
Just my 2 cents. But I agree too much trouble. Just decapping the spent 209 and cleaning it out would be a pain.