Study shows that dogs are healthier when few once a day.

[Catherine]

I am just trying to picture your place in the morning. It must be a real panic until you feed them. What about the birds, do they join in?
You could do your own feeding study. You have enough willing participants, that is if you are feeding them. If you tried to skip a meal you would have a riot on your hands. 

Your dogs get a good quality food and you give a healthy amount. Your dogs get exercise too. That has got to be a factor in their feeding needs. 
Overfed and under exercised dogs might do better with less food. They would definitely do better with more exercise.