Dimension D, all-button-mode

[PaleSkinnySwede]

I've tumbled down a rabbit hole.

I was playing around with some effects and noticed that I couldn't active the "all-button-mode" on Arturia's rendition of the Dimension D.
When I read the manual to understand if just pressed the wrong keys they say:
"in the original units it is possible to press more than one button, or even all the buttons, this doesn't give the user any extra advantage. In fact, when you press more than one of the first three buttons, the button with the highest order is the one that gains control, which means that, if you press 1 + 2 + 3, the effect obtained is the same you get when pressing just 3. The only button that adds something to the effect is button 4, both in the original units and in the emulation."

My UAD Satellite is tucked away on the attic but I remember that you could press all four buttons. I then also found that Overloud has done a version of the Dimension D but named it Gen Mod and you can press all four buttons on that one too.

Is what Arturia claims the truth? That it doesn't matter if you press all four because it'd be the same as pressing 3 + 4?

I've tried googling but my Google-fu is failing me tonight.