And I argue FOR carbs pre-workout because they lower the cortisol response to training. And most bodybuilders and tons of powerlifters are now using carbs pre-workout and their workout do not suffer.
But you know why catecnholamines levels do not rise as much? Because you do not need to mobilize stored glycogen. catecholamines and cortisol are increased during a workout to mobilize stored glycogen. But if you consume carb pre-workout then there is no need for as much mobilization hence the lower output of cortisol and catacholamines. And in the great scheme of things it is actually a great thing for gains.
Of course one could argue that a lowered catecholamine release could make you sluggish. While it sounds logical in theory, in practice we just don't see it. Otherwise you would see tons of NFL, NBA, MLB and NHL players fall asleep in the second half of their games because they drink carbs throughout the game.
The fact is that the body releases what it needs. During training even if you consume carbs, if you go hard at it there will be enough catecholamine release to increase your heart rate and the contractibility of your muscles.
One of your biggest issues, and I mentioned it in the past, is that you seem to be easily swayed one direction or another just because one "expert" says something. Listen, experts have their own opinions and they will often be drastically different than that of other experts. So if you are easily seduced by these experts you will always spin your wheels, questioning whether you are doing what's best or not. This of course will hurt your gains.
You should not be seduced, or blindly believe what any expert (including myself) says. You should listen to what they say but then look at the physiological facts to see what will really work.
Sometimes expert quote only the physiological facts that prove their opinion. So you have to dig a little deeper.
Let's take the example you mentioned. It's TRUE that catecholamine and cortisol increase during hard training. So one could make the argument that you DO NOT want to inhibit their release otherwise the quality of the workouts will suffer because they are supposed to go up.
Of you could ask yourself WHY are catecholamine and cortisol increased during training. They are increased mostly to mobilize stored energy. OF COURSE if you consume energy (carbs) pre-workout your cortisol and catecholamine release will be lower. It is lower BECAUSE YOU DO NOT NEED TO MOBILIZE AS MUCH FUEL because you have some readily available.
It's NOT the catecholamine/cortisol that you want... it's the ENERGY. The catecholamine/cortisol release is not the goal, it's a mean to a goal... and the goal is the energy availability. If you can get the energy with a lower catecholamine/cortisoil release you will be better off (faster recovery, less adrenal stress, less negative impact on testosterone production).
Now, if fat loss where your only goal the argument AGAINST carbs pre-workout could stand in that it might decrease fat loss from the workout. But I would counter that argument by saying that fat loss is acheived through diet and energy systems work, not lifting. Lifting is there to build or maintain muscle. So even while dieting down I personally recommend having carbs pre-workout. During a fat loss phase your cortisol already tends to be elevated all day (because of the need to mobilize energy), the last thing you want (if muscle mass is important to you) is to have even more cortisol release during your training.
I want to say that Charles and I have a good relationship. He was my first mentor and to this day he is the one who had the greatest influence on my principles. But we don't agree on everything and this is one of the topics we don't agree on. He often says how much more important establishing an optimal hormonal milieu is for body composition improvements than caloric intake and expenditure. Then why would something that leads to a much lower cortisol level be a bad thing? But that is just my opinion.