As far as your argument, it may be true if you are taking a picture purely for art's sake but if you are trying to sell a product it is the wrong way to go,
He is right
So if what we're selling is one maker's design sense in contrast with that of a zillion other makers, it may also be important to make an advertisement that stands out from the rest of the crowd. In this way, the differences between all of these knives can be more clearly observed. The magazines are filled with the same old knife advertisements, all adhering to one of perhaps three different design approaches.
and he is right too.
It depends on how you're trying to sell. Dr. Lathe's knives are not common commodities. They are exotic specialties.
Personally, I am tired of knife mug shots. Boring pictures that all look the same.
In the movie, A River Runs Through It, the father teaches his two sons to fly fish. "Casting," he drills them, "is an art practiced on a four-count rhythm between ten o'clock and two o'clock." And thus his boys learn to cast with consistently-good results. Consistency is the father's goal. One boy then goes off to college where he doesn't fish for years. The other stays home fishing most every day. When the first boy returns, the two naturally go out fishing. The first boy quickly returns to the consistent casts his father taught him, that four-count rhythm between ten and two o'clock. And he has good results. But, then he looks over and sees his brother who has broken free of the four-count rhythm and developed a wonderful and bold style all his own.
"Knife photography is an art practiced on a four-count rhythm between ten o'clock and two o'clock. First count: put the knife flat on a simple, neutral background with the tip at either ten o'clock or two o'clock. Second Count: Light the knife perfectly evenly. Third count: Focus exactly on the knife and compose the picture exactly centering the knife as the knife runs diagonally thorugh the center of the frame. fourth count: Click the shutter."
One, Two, Three, Four. One, Two, Three, Four. One, Two, Three, Four....
And just as those fly casts are consistent, so the pictures start to become consistent... they become a commodity. One might say "duplicative," or even, "monotonous."
That's why I try to break free of the four-count rhythm every now and then, change with the composition, experiment with the light, try a different angle, anything to add some creativity, some excitiment, something to make the picture different.
It's art, yes. But can it be advertising too? If it catches your eye, if it makes you stop and look, if it stands out from the crowd, then yes it can. It can carry the message: this is not just another commodity picutre of another commodity knife; this is different.