Keybooard and Mouse. Everytime. I have the same question.

How much do you type in a day that moving the hand to the mouse is a productivity loss? I spend a lot of time staring (thinking, planning) than typing. So, moving my hand to the mouse and back barely has any impact.

It has a pretty profound impact on me, since the only way I can use a computer is using a screen reader, which works primarily using a keyboard. It can read things under the mouse, but it is not at all a comfortable way of working.