So if you know on this screen you need to hit F1, and that on the next screen you will have to hit X, then on the following screen, you need to type in the SKU number, you could simply issue as fast as you wanted: F1-X-4112295[ENTER], and take your mind off it while the system would just go through the whole experience successfully at its own pace.
With "better" GUI/mouse based systems, you have to click here, wait... wait... wait..., now click there, wait... wait... wait..., then click there and type in your SKU. Your attention needs to be on the screen at all times in order to wait for the UI and aim the mouse.
Next time you go to your bank web site to pay a bill, think to yourself: Wouldn't it be nice if, rather than navigating their cumbersome UX, you could just hit a known string of keystrokes that you memorized, hit enter, then walk away to get coffee while all the Javascript and page reloading chugged along and paid your bill?