Well, the first thing that comes to mind you can't do with KB+mouse is moving around at like 10 different speeds. You also can't walk down easily those spiral staircases found in the Nord ruins, and you certainly can't lie back and relax like you could do with a controller. Once you get used to it [and it took me a full month for this] all those things alter completely and forever the way you play the game. Self control has little to nothing to do about it.
You can. And if you can't, you have badly adjusted the sensitivity of the mouse. AFAIK, it's the controller the one which in fact has only 1 speed. And again, I can walk down those spiral stairs just fine, even with a single, slow, prolongued movement.
And again, self control is
all what's about with it, wheter you believe it or not. The proof is that you CAN go slow with K/B if you want. All you must do is, well, to do it.
BTW, just stating the fact...I always play with max sensitivity, and I'm still being able to do such slow and careful movements like the stairs' one
