Scene luminance has nothing to do with exposure.

it doesnt matter as the ends are still locked. same when you adjust curves in PS to gain more contrast.

You are terribly wrong.
On a side note, the tone curve applied to the image isn't the one applied to the horizontal scale.

when have you ever applied a tone curve and clipped the ends of an image ?

when have you ever clipped the ends of a histogram with colours ? because if you have you need to relearn how to take/process an image.

this is a good example why sony zebras are the most accurate way to expose colours bar none.

Sometimes several times a day. Could be even several hundred.
"a tone curve only effects the middle of the histogram not the ends" - that's wrong, clipping or not.

You have no idea what you are talking about ~<:-)

I can only think of 1 instance when it is the proper way to print. and thats printing a B & W image. there is no other reason.

so you keep saying, post an image with a purpose blown out head shot 😂

Post any image of yours lets see if you live up to your keyboard theroy perfectionism.

Consider off-white background, and generally use your imagination.

sorry i never blow out backgrounds i always leave them at 246 so the printer can lay ink. Have you ever seen a print with a pure white background and the object/subject is floating in space ? very wrong.

Consider composite / extraction, consider what a customer may want, and generally use your imagination.

I think your assertions are locked on the tools you've used. The end control points of the curve tool I use can be slid along either axis...

Even with them set at the far corners, there can be significant effect with slope in the corners. That's the basis of the filmic curve, which has a toe (left end) that starts shallow but almost immediately changes to a steeper slope, far before you can really see it in a curve plot. That's to emulate the so-called "crisp blacks" of film. A good read on it:

filmicworlds.com/blog/why-a-filmic-curve-saturates-your-blacks/

Adobe RGB image histogram

No clipping.

Image converted to sRGB, absolute color:

Lots of clipping on the color channels.

Sadly I have a feeling that we need to start from the beginning with Don, the very first is what a histogram represents.
This would probably not work as seen with his refusal to learn and to throw away his preconceived notions on other subjects.

No "probably" about it - it definitely will not work and his preconceived notions on other subjects will remain fully intact ...

... and wrong.

affects and ...

... hogwash. I'm not even going to bother with an example ... it would be waste of my time ..