so you can just close your eyes and wail on the keys?
Yes.
Blind?
I'll put this in the easiest way I can think to explain it to you:
1) Take the "X" key off the keyboard
2) Take the "C" key off the keyboard
3) Put the "X" key where the "C" key was
4) Put the "C" key where the "X" key was
Now, that won't affect me, because I know where the X and C keys are without looking. So if someone mixed them up I wouldn't notice unless I looked at the keyboard.