"What evidence do you have that too many calories dont result in weight gain?"

You should read the parent again, more carefully. The point is not that that is not a true statement, the point is that is a vacuous statement, and therefore, the wrong question. It is not controversial that things that cause weight gain cause you to gain weight, but it's not a useful statement for either science or engineering, and we have collectively wasted an awful lot of time and research while laboring under the delusion that this was some sort of actual explanation, rather than a mere restatement of the problem.

Thank you. How the above comment poster somehow read that I don't think excess calorie consumption is part of the chain of weight gain is beyond me.

As you can see from the number of comments on this subject there is a lot of confusion subject. We make things difficult by talking about bad foods, partitioning, healthy food, etc. People get fat from eating more calories than they burn.