I have got to learn to use AE LOCK HOLD (H*). Excited every time I read about someone using it, but never have. Thanks!I'd say AF precision and consistency is the biggest improvement of the R over the 5DIV, particularly at wide apertures.
The other big step up is with exposure. The EVF is so good at showing exactly what the captured exposure will be that it frees up fingers and mind to compose more easily and to nail desired exposure exactly. EXACTLY. By using spot AF, moving the spot zone slowly over different parts of, say, a person's face, the shadow/highlight balance can be locked in with AE LOCK HOLD (H*).
"Stone age" might be a rhetorical flourish, but "paradigm shift" is not much of an exaggeration at all. Seriously. Photographers with years of experience might already be nailing exposure consistently, and they might be satisfied with AF. (BUT, until you see the AF improvement of Canon's mirrorless, you just can't understand how much better it is.) Newer photographers, however, don't have as steep a learning curve, and can start capturing and creating faster than before. Much faster, I believe.
This is why some of us who have made the move to mirrorless are so very enthusiastic. Hopefully not to the level of crusading, but definitely stoked!
See? I'm this excited with just the R. And still patiently waiting for an R5!