In other words, James didn't choose this fix, so it must be wrong.
1) A hole punch doesn't actually punch out a slug of material, but deforms the metal to stretch out a hole.
2) The slot is parallel to the torsional forces exerted on the shaft, therefore not likely to promote failure. Were it perpendicular to the exerted force, then you should worry.
Let me guess: you like the LNE fix, so anything else is inferior and wrong? Yeah