increases chances is subjective. For you personally, it definitely doesn't hurt to have it written on your application. However, those who didn't go to SS will in no way be penalized for not getting selected. And your attending SS isn't actually putting you ahead of someone else. Put it this way; if you and another person; same school, same sex, same exact classes, same exact grades, same exact SAT/ACT scores, same sports, same leadership, same volunteer, same exact EVERYTHING that you can possibly be "Graded" on; and the only difference at on in the entire world was that you went to summer seminar and the other person didn't; then it MIGHT give you the edge.
Realize that there is approximately 350 summer seminar attendies per session. Normally there has always been 2 sessions. I think this year there are 3 sessions. So at the most, the academy can only let in about 1000 applicants into summer seminar. That is about 10% of all those applying to the academy. And application of summer seminar closes halfway through your junior year of high school. So the academy doesn't even have an application on you. There is no way that the academy is going to penalize someone because they didn't go to summer seminar. And if they can't penalize, then there's no way they can give "Extra-Credit" to those who DO attend. That would be the same as penalizing those who didn't go.
But, there are a couple of things that by going to summer seminar with definitely benefit you and increase your chances of getting accepted.
1. Many who attend SS and realize they really want the academy, become much more motivated after returning from SS. They go "Balls to the Wall" with their application and get it done much sooner. This WILL help your chances.
2. If your ALO has 5-10 applicants, and you went to SS and most of the others didn't; your ALO's interview and nomination of you will probably be more positive. This CAN help your chances.
3. Your representative/senator who you will be looking for a nomination from, will definitely look more positive on your attending SS. And if you're the ONLY one of those applying for the academy needing a nomination who went to SSm that WILL look good upon you and help get the nomination.
So while attending SS itself does not increase your chances of getting an appointment, it will help you get better recommendations and possibly nominations. This is not to say that not going is going to hurt you. If you went to SS and didn't do a lot of leadership activities, and I went to Boy's State and am Class Vice President, then your SS isn't going to automatically make mine less important.
The hardest thing for people to understand about the appointment process is that it's a "TOTAL PERSON" assessment. Also, nominations most times are from members of congress. Which means that most candidates are ONLY competing with others in their state and district. There are people who have had excellent grades and very good scores, who did NOT get a nomination and didn't get an appointment. Now, if everything about you walks on water, and your member of congress just can't give you a primary nomination for numerous reasons, then the academy can help you get a nomination from other sources if you're that good. (If you do your application early enough, that's where an LOA comes in). So it is not uncommon for an applicant in "STATE A" with a 3.75gpa and their resume to get an appointment; while another candidate in "STATE B" who has a 3.80 gpa and a BETTER resume all around, to NOT get an appointment. They aren't competing with each other. There's basically 3 levels of appointments. (There are more, but for the average, there's 3). 1. Those who have nominations from sources outside of their state; and their application walks on water. They usually receive an appointment early. 2. Those who's application walks on water and the academy gives them an LOA. All they need is ANY nomination and they get the appointment. 3. Then there's the REST of the normal applicants. You're hoping to get a primary nomination which gets you in. If not, then you do compete with the rest of the applicants.
It's a very indepth process. Summer Seminar is mostly beneficial to you personally. If you really like the idea of the academy after attending summer seminar, then you're probably going to be more motivated, do better in interviews, will display a better attitude and glow about yourself. Best of luck.... Mike....