Yeah, just pre-plan your day, check the pie chart, and see if you want to change anything.
Mid range of everything isn't necessarily going to give the right percentages.
I think it's more important to worry about the ranges than the percents though. It's not likely you'll be way off and remember even that pie chart was made from broad percent goals (eg Carbs at 50% is actually something along the lines of 40-60%, so if you're getting say 57% carbs all the time, that's still within a healthy guideline).
Deb, in New Zealand