On my god, not only no but hell no.
When I was a teenager I made a balancing disk for my dad’s lathe with a disk of ply screwed to the back of the chuck to which I attached lumps of tool steel with screws and tape to balance a large burr.
Slow it was ok, fast was also ok till with a bang one piece of steel flew off, at that point the lathe started walking across the floor, some of the other lumps of steel also flew off, one dented the steel garage door, one went through the plasterboard of the wall and another piece is somewhere in the ceiling, eventually it walked far enough that it pulled the plug out the wall and the lathe stopped.
That cutter block in a router would be almost as stupid.
Who on earth paid anything for it, not to mention over £80?!
Aidan