In the Calories Summary I can see:
Energy: 514.9 (371.3 net) kcal / 1593 kcal (32%)
What does the net figure do?
Net energy should be however much energy you have eaten minus however much you have used up in the exercises you have logged. Theoretically, you would want your net energy to reach 100% for your goal. Cronometer seems to use the energy consumed for the % calculation, though.
The energy line, by showing both energy and net energy with different tones, does make it easy to take either figure to the 100% end of the display scale. So yes, showing both does have a function, I'm happy with that. Thank you @Vickie