I have also found that knowing exactly what you want is of no help.
For example, if I order (inside, not drive through);
"No. 3 combo, medium size, regular fries with a diet coke to go."
The following exchange always happens:
"So, that was a No. 3 combo?"
"Yes."
"What size?"
"Medium."
"Regular or curly fries?"
"Regular."
"What kind of drink?"
"Diet coke."
"For here or to go?
"To go."
<sigh>
I have given up saying the whole order at once, but sometimes, ironically, if I am in a hurry, I forget and end up engaging in the dance of fools quoted above.
MotionMan