[Splines]

In my experience, you can get as far as needing to hit "I agree to pay" and scribbling on the touch screen.

Entering in/scanning your customer loyalty number and pulling out your credit card and scanning it (and pressing credit/debit) is what I've been able to "preload".

One other neat thing I've noticed is that at my Costco gas station, I can pull the pump out and select my gas type while simultaneously scanning my costco + credit card. I usually try to time myself with the person in front of/behind me to see if I can start my pump faster than them. I usually win :)