I agree that the testing of blades is important....how else can you prove that the blades you produce have quality or the forging techniques you employ are the 'best'. Historically speaking...many blades were tested.....to find out, in the heat of battle, that your blade was say,...badly tempered and shatters, would be a test...too late
Using an 50 calibre machine gun.... is a little extreme ....but visually it is a spectacle......a case of old weapon technology versus new.... no problem there......unless the katana is historically significant.....then thats a different matter