Each of the 4 scoop blades are probably 1/4" in height from center line. Add that to the 1" cutting diameter and it equals 2". Tissue trauma is tissue trauma. It doesn't matter if it's all on the same plane or perpendicular to the primary cutting blade. I work as a Flight Paramedic. I've seen people who have been stabbed once and I've seen people who have been stabbed twice. The people who were stabbed twice had more tissue damage and more blood loss.
But yeah, I can understand the skepticism of a 1" cutting diameter. Although, when we consider that there's two separate 1/2" cutting diameters perpendicular to the 1" cutting diameter, the ability to create trauma is there. The downside to that design though is, the shape of the entrance and exit holes isn't conducive to good blood trails. I've had great success with Annihilators in the past, but blood trails haven't been the easiest to follow. On an accurate well-placed shot, its never mattered though.
My current setup is Iron Will Wide 125's. Their main cutting diameter is 1 3/8" and have a 3/4" bleeder. Total cutting diameter is 2 1/8". I don't think 1/8" in total cut makes much difference ... but, the 3/8" wider main cutting diameter DOES create a larger entrance and exit hole, and the tearing that accompanies a well-placed shot results in a far better blood trail. A 1 3/8" wide cut vs. a 1" cut is more confidence-worthy for when the time comes and Mr. Murphy shows up.
The other thing about the Katana is re-sharpening. They're apparently advertised as tougher than A2 and with better edge retention, but easier to sharpen. You can't have both. A tougher, harder edge will be harder to re-sharpen. An easier to sharpen edge will not hold up as well. And I'm curious to see the process for resharpening these. In my opinion the sharpness of the bleeders is just as important as the main blades, and these bleeders look like they will present some challenges. I prefer to use sharpeners instead of flat stones. I kinda suck at sharpening things, and the sharpeners like the Work Sharp Pro Precision Adjust and it's predecessors have provided me the best results so far. I'm not sure if the Katana can be sharpened in that style of sharpener - maybe, maybe not.