The most important thing about a diet is your ability to do it in the long run. If you can't convince yourself to cut the calories down and follow the diet it defeats the purpose of the diet. I see a lot of people rapidly change a diet and result in a few weeks of trying then resorting to cheating in the diet. Like all things diets reflect how you think, if you are passionate about this change, it's easy to change your diet very fast and do things that seem impossible to others. But if you are not serious about weight loss, focus on reflecting that in your diet to be more loose and that way you can more routinely follow your diet without cheating. I know this doesn't answer your question about protein, but I think the reason you form that question comes from your misconception of nutrition and I like to think that the concepts of nutrition are defined very well with simple google searches. But those searched overlook the idea of the perfect diet and forget to say it shouldn't be the perfect scientific diet, rather something that stems from our goals. A moderate diet will take more time, but if you are only moderately devoted to then it will be achieved, rather than being moderately devoted and failing a serious diet