[robinson7d]

The difference that I see between 3D touch and right click is that one adds functionality to the same input mechanism, and the other adds a new button. Assuming that every action can be done with only standard (non-3D) touches, or only left click, a nontechnical user navigating an app is basically simplified into:

- Touch screen users use the app, and never/worry know the shortcuts that they're missing,

- Mouse (w/ two buttons) users first wonder which button the have to use, then learn to use the left one. They stick to clicking that leftmost button, but occasionally look, confused, at that other button.

(Ignoring power users with the assumption that they get used to either.)

On the other hand (as a counter-point against my own thesis), I've never noticed them shying from cmd, ctrl, alt, fn buttons on keyboard, which seem to present the same issue. Perhaps that's just because keyboards have so many keys already?