Does AP/EA really help you get into the school?

I saw a post on this website saying if you attend the AP/EA program and do well in the courses, you will most likely get in. Is this true? I want to attend the program because it offers high level courses, but is this true?

I Have heard of one student who put School of CS as his only choice who got two As in discrete math and a second level programming class in the CMU AP/EA summer school who was already rejected for binding ED this year. My son also has two As and applied RD, and has not heard back yet, but my sense is at CMU its best to put a second choice if you are interested in computer science, such as school of engineering as there are very few seats in computer science at CMU. Getting As in summer school does not seem to be a guarantee, based on my ONE data point! but may depend on your major, and the strength of your application. The school of science is much easier for admission than either CS or ECE or any other engineering major.