personally
Don't think you can take anything in isolation, if something always works for you over and over then great. Sunday night I did a run and I was flying (at 8pm). At 5pm I had a monster coffee, so big it had two sets of handles, and a chocolate cake. Other than that just a scrap of mashed potato the kids didn't eat. I still felt wired from the coffee after the kids were down so did the run, had not planned to, and ran 4.5 miles at 7:20 pace, quick for a training run or a race for me. Whether its down to the coffee we'll see, I'll do another test sometime. When I used to run in the past years ago I swore by millet. Not very tasty but good ballast, not unlike porridge I guess. Like previous poster my morning carbo load is a glass of water as I fit runs in before kids wake up, I feel significantly slower then compared to runs later in the day.