Ah. I see where you're coming from. You don't accept the premise that a regulator valve will operate with lower pressure than a needle valve.

The only real way to prove that a regulator valve can operate at a lower pressure than a needle valve is with testing. One could:
a) Take two comparably rated stoves, one regulator valved, one needle valved, and run them with identical canisters at temperatures where the internal canister pressure will be reduced. With the valves 100% open, observe any difference in the flame between the two stoves.
b) Hook a manifold to a single gas source and run it through both stoves and observe how each valve type's flame responds at a given pressure. One would be allowed to adjust the valve settings at will during the test.

I have been intending to do a test of type "a" myself since I have all the necessary equipment. I just haven't had time.

However, a test of type "a" has already performed for us: Take a look at the video from Soto in my original post. Note how far they open the needle valve on the non-Soto stove. It's fully open. Next note that the flame sizes are equal at the start. Then note that while the flame diminishes on the conventional burner, that the lower pressure does not significantly affect the output of the Soto burner. Clearly, the regulator valved burner can run at a lower pressure than a conventional burner.

While the video does demonstrate the Soto's technological advantage, my criticism of the video is that Soto doesn't mention that the temperature range is very narrow (at which a regulator valved burner will outperform a needle valved burner -- only about 5 degrees Fahrenheit/2.5 degrees Celcius) in width.

Not only do we have a test of type "a" available to us, we also have a test of type "b" available:

Notice how far he opens the conventional burner on the left. It's wide open. Then watch as he reduces the pressure by lowering the temperature of the fuel. In the video he says "ambient" temperature which of course is incorrect. He's altering the temperature of the gas (not the ambient temperature) which reduces the gas pressure. Again, a clear advantage on the Soto's part at lower temperature/pressure is demonstrated.

Notice though the temperature markings (in Fahrenheit) on the gauge. He never takes the gas temperature below about 20F/-7C. He's playing to his stove's strengths, that narrow band at which his stove will outperform a conventional burner. So, while a regulator value does have an advantage, it's a modest one, spanning about a 5 degrees F/2.5 degrees C range. Had he dropped the temp to 0F/-18C, the Soto micro regulator would be as dead as a door nail, just like a conventional burner.

To my mind, the real advantage of a regulator valve is getting the most out of your canister of fuel. Here, I'm relying on my experience with another regulator valved stove, the MSR Reactor. When I burn through a canister with a Reactor, that canister is empty. When I use conventional needle valved stoves, there's always a bit of fuel left in the canister.

HJ