My parents used to do a version of this when I was a child. They'd make coffee, add a little coffee on top (about a quarter of the amount normally used), and th

My parents used to do a version of this when I was a child. They'd make coffee, add a little coffee on top (about a quarter of the amount normally used), and then brew that mixture of grounds. This was done in a drop machine: I can't remember if they did this with the percolator. They stopped when they had enough money to use fresh grounds daily. If it wasn't inferior, I'm not sure they would have stopped.