with emacs and ido-mode enabled I press Ctrl+X B to open a buffer, Ctrl+X F to open a file, I typically type 2 or 3 characters from the filename and emacs gives me a list of matches (with autocomplete), usually the first suggestion is correct and I press return to open the file.
I barely need to think while I do this, there is no visual clutter on my screen, and I can usually finish the before someone could take their hand from the keyboard to the mouse and move to the filetree