When you have gastric bypass or something similar, it makes your stomach very small so that it can only hold a small amount and you will feel full after eating hardly anything.. ok so you eat minimal and lose big right? Well i dont have a problem eating very little, but then im told im not getting enough calories in... Why is it ok for these surgeries to restrict such a large amount of calories but its not ok to eat such a small amount otherwise? Any insight would be greatly appreciated! Thanks!!

Your weight loss and subsequent transition to more-normal eating is closely supervised after weight loss surgery, IIRC. You could expect to get similar results with a physician-supervised VLCD with a good transition plan if you stick with it. A do-it-yourself VLCD is unlikely to give you sufficient nutrition or the skills you need to successfully maintain without regaining.

Another thing to bear in mind is that WLS generally will take someone from morbidly obese to less-morbidly obese, not from overweight to normal weight. You can safely (in terms of maintaining lean mass and in terms of avoiding metabolic slowdown) lose from 400 pounds to 300 pounds much faster than you can lose from 150 to 100, for instance.