Believe me I know, I grew up on a grain and livestock farm, took a meat science course at UI, have actually judged cuts of meat, have raised freezer beef and have done competition and commercial BBQ for years. I’m a meat and food mad scientist. My relationship with meat both large and small has been a long and intense one.
The reason the pieces in that photo are rectangular is that the steak is thicker than the surface area of the cubes I’m trying to make. I would have had to slice the steak in half lengthways to avoid that. Which I actually managed to do last night. You can see the cubes are much smaller on last night’s effort, as the steak was thicker and easier to work with.
If you’re trying to argue that the pieces need to be smaller on the across the grain cut I agree. Those cubes aren’t as small as I normally try to make them. Even after searing the steak was so soft that it was hard to cut into any smaller pieces despite using a freshly sharpened knife.
But if you’re arguing that it matters which cut was made first I’m not buying it.