When I was 16 I worked at Mickey D's for about 6 weeks. Started on Lot & Lobby cleaning table's and crap, then got "promoted" to fries. You would cook a whole fry basket at a time, then dump them out of the fryer into a big heated hopper and shake salt on the whole thing. Then the countdown begins. You might get fresh, you might get 15 minutes old, which is what I think the timer was set for.
So, when someone thought they were going to be cute and ask for no salt thinking they were going to get fresh, here's what I would do. Take an order's worth out of the pile in one of the hoppers, put it back in the fryer for like 30 seconds - BAM! There's your fresh order of no salt fries.....