I've been going low-carb recently, and I've been feeling pretty damn good. I just booked up Ruckel Ridge with a breakfast of chorizo and eggs to start. Throughout an eight-hour day, 12 miles, up and down 4000 feet in 90 degree weather, I was eating coconut oil, ham, jerky, nuts, and about 3 shots of Hammer Gel, with electrolyte water (no sugars). Was this perfect? No. In hindsight I could have probably used a little more carbs during and post, which slowed my recovery. I think too many nuts, which I have a hard time controlling myself from eating just a little, have more fiber than I need to be digesting during a long hard day. It was a rushed camping trip, a last-minute idea with the family, and I didn't pack a single nalgene, so I would rather have carried a protein mix to take in liquid form rather than eat as much solid food as I did. But I still did pretty good for myself, no bonking, no nausea, no dragging other than the expected fatigue(haven't been out that long in awhile). But I think a good dose of protein AND FAT is essential to a good breakfast which doesn't have to be big; I agree with the point that it's just the first fueling.
One research study found that low-carb athletes do just fine when operating at or below 60% VO2 max in endurance events, if you're above that, higher-carb athletes perform better, but that's not to say low-carb athletes can't still perform. It does lend more importance to fat and protein in the athletic diet whatever your level.
I'm not recommending a total low-carb diet, only that one explore the arguments. It used to be the wisdom that carbo-loading is good. Now, it's not, but the conv wisdom says carbs should be the base of your pyramid in any case. Now, Hammer and other endurance specialists are recognizing the importance of protein and fats in endurance events. The Bicycling Magazine article's title has to be a shameless riff on Gary Taubes' 2002 NYT Mag article "What If It's All Been a Big Fat Lie?" which questions the notion that dietary fat has anything to do at all with heart disease and obesity (I think his book Good Calories, Bad Calories argues well enough that it doesn't, as well as dispensing with a number of our dietary myths, including scooping BM on the calorie equality fallacy). The BM article for example still holds to the myth that lean meat is better for you than fatty. The challenge to the carbo-loading ideas has been around in the low-carb athletic community for awhile now.
There's no point in complex carbs for an athletic event (hey, I dig Scottish oatmeal, too, but it's not necessary). It all has to break down into glucose. I recognize the advice as being opposed to something sugary, which is what some people can work well (enough) with, (once climbed with a guy who had to have his Cap'n Crunch as he decried my sausage), but they contain fructose as well, and that's a whole nother topic. The maltodextrin in a gel is all you need as far as carbs go, because you need it right now, not in an hour or so while your glycogen stores (1-2 hours worth) are being depleted and you're wasting blood flow to digest fiber.