The sugar you eat in Coke is going to send your blood sugar / insulin levels to sky rocket. High insulin levels cause fat storage. You could "lose" weight, but your body composition (or body fat percentage) certainly won't improve.
Insulin levels cause fat storage in order to lower blood sugar levels. If all you did was chug two 2-liter bottles of Coke, you'd temporarily go through lipogenesis, then go back through lipolysis to pull the stored calories back out for use later in the day.
Insulin doesn't magically make you fatter if you're consuming the same number of calories. A high protein/fat diet is more satiating and you consume less calories, but insulin is not evil.
Most people when they say they want to lose "weight" meant they want to lose "fat" and improve body composition.
Focusing solely on calories in / calories out omits any effects hormones have on fat burning / storage.
In your scenario - yes - if someone drank 2000 calories of coke and that's it, they might not get "fatter", but that's not how real life works.
99/100 times, that person who drank 2000 calories of coke is going to be starving shortly afterwards and isn't going to simply "fast" and let lipolysis take place. Instead, because sugar causes ridiculous cravings - they're probably going to crack and down another 1,000 calories of another carb intensive, sugary food ('cause cravings) until their calorie intake exceeds their calories used and their hormone levels are thoroughly trashed.
I like hypothetical scenarios as much as the next guy, but focusing strictly on calories in / calories out and ignoring hormone imbalances, cravings and other real-life factors are typically symptoms of someone who reads lots of books, but hasn't has too many real life case studies to work with.
Your initial assertion was that high insulin levels cause fat storage (really, insulin causes blood glucose to drop, either through glycogen uptake in muscle tissue or lipogenesis and glucagon causes it to rise via the opposite mechanisms) in response to the prompt:
> Would you lose more weight drinking two liters of coca-cola a day or eating the equivalent total calories in a high-fat protein rich food?
I'm sorry that my made-up scenario isn't the same as your made-up scenario, which now has a ton of conditions and it suddenly "real life".
Yes, in real life, someone who consumes 2000 liquid calories is going to be hungry. As is someone who consumes 2000 calories of bread. Or donuts. Or anything else which is digested rapidly (and this is exactly why I brought up satiation).
But this isn't a "hormone imbalance." This is, in fact, absolutely typical and ideal action from hormones doing their job, unless your made-up-real-world scenario now also involves people with insulin resistance. Because 2000 calories is 2000 calories, and while studies show that the normal metabolic range is +/- 200kcal from calculated bmr, "hormones" are not some wild card. Men eat more (higher bmr, testosterone promotes liposysis and better nutrient partitioning), but a man or a woman doesn't go through massive hormonal changes on a regular basis, and consumption of an equivalent number of calories from different macronutrient groups can be expected to have about the same effects on composition (unless it's all protein, in which case you get to worry about dying).
If you want to discuss hypothetical scenarios (2000 calories of sugar vs equivalent total calories in a high-fat protein rich food), discuss them. But don't change your stance when someone questions you.
The problem with people who do things like drink 2 litres of coke, is that they become insulin resistant. Meaning they produce a lot more insulin than required, as thier bodies ability to gauge how much insulin is thrown out of wack (by the spikes in sugar).
Now when you have something that only requires 2units of insulin, your body outputs 4 (because of insulin resistance) and now fat cells are being created when they shouldn't be. (Because insulin is what regulates fat storage, i.e insulin takes the sugar out of your blood by shoving it in a fat cell).
Keep this up, and you eventually end up diabetic.
You are both saying the two different sides to the same coin.
EDIT: To be clear - If you have regulated insulin (by controlling carbs and suger) you will gain less fat (but lose it normally). If you starve your body of those sugars in the first place you will lose more than you gain (regardless of insulin). This is why WeightWatchers works, and why Excercising your arse off works, and also why Paleo/Atkins/Low-carb works.
Calories in > calories out can "work", but it's not an efficient way to address body composition - especially with people new to nutrition because of the hunger / craving factor that invariably comes up.
Also - continually drinking 2000 calories of coke is going to lead to chronically high blood sugar / insulin levels and will degrade their insulin sensitivity over time.
Zero fat, high sugar diets have been a proven way to get lean for decades. If you put people on a very low fat diet with a good amount of protein (say 90 grams), you can allow them to eat sugar and starch ad libitum and they will get lean. No need to count calories.
https://www.drmcdougall.com/2013/12/31/walter-kempner-md-fou...
6 . Hellerstein MK. De novo lipogenesis in humans: metabolic and regulatory aspects. Eur J Clin Nutr. 1999 Apr; 53 Suppl 1: S53-65. 7 . Acheson KJ, Schutz Y, Bessard T, et al. Glycogen storage capacity and de novo lipogenesis during massive carbohydrate overfeeding in man. Am J Clin Nutr. 1988 Aug; 48 (2): 240-47. 8 . Minehira K, Bettschart V, Vidal H, et al. Effect of carbohydrate overfeeding on whole body and adipose tissue metabolism in humans. Obes Res. 2003 Sep; 11 (9): 1096-1103. 9 . McDevitt RM, Bott SJ, Harding M, et al. De novo lipogenesis during controlled overfeeding with sucrose or glucose in lean and obese women. Am J Clin Nutr. 2001 Dec; 74 (6): 737-46. 10 . Dirlewanger M, di Vetta V, Guenat E, et al. Effects of short-term carbohydrate or fat overfeeding on energy expenditure and plasma leptin concentrations in healthy female subjects. Int J Obes Relat Metab Disord. 2000 Nov; 24 (11): 1413-18. 11 . McDevitt RM , Bott SJ, Harding M, et al. De novo lipogenesis during controlled overfeeding with sucrose or glucose in lean and obese women. Am J Clin Nutr. 2001 Dec; 74 (6): 737-46. 12 . Danforth E Jr. Diet and obesity. Am J Clin Nutr. 1985 May; 41 (5 Suppl): 1132-45. 13 . Hellerstein MK. No common energy currency: de novo lipogenesis as the road less traveled. Am J Clin Nutr. 2001 Dec; 74 (6): 707-8.
You must have a strange view of "normal conditions." Fat is actually a more-efficient, longer lasting source of energy than carbohydrates.
>De novo lipogenesis in humans: metabolic and regulatory aspects. http://www.ncbi.nlm.nih.gov/pubmed/10365981
"Eucaloric replacement of dietary fat by CHO does not induce hepatic DNL to any substantial degree. Similarly, addition of CHO to a mixed diet does not increase hepatic DNL to quantitatively important levels, as long as CHO energy intake remains less than total energy expenditure (TEE)."
You need to read more than your confirmation bias-laden sources if you believe these things. Stop reading Taubes and pick up Aragon and McDonald. The best way to actually learn the truth is to read something that runs counter to your viewpoint and analyze it.
The best way to learn the truth is to experiment for yourself and see what actually happens.
I'm always willing to read counterpoints - but I've yet to see anything that counteracts the fact that high insulin levels prevent the fat burning process from taking place. Insulin isn't evil and if you time it right - it can actually be quite beneficial, but chronically elevated insulin levels are a problem for people trying to burn fat.
I'm happy to read any links you want to send my way. In the meantime, I suggest you take a look at John Kiefer's work at http://body.io to see how your hormone levels can have a bigger effect on your overall body composition than straight calories.
It most certainly would improve. He might have a better result with a more reasonable diet, but he would still see a significant reduction in his body fat percentage if he stayed on the diet long enough.