I think to Bullet's point, a candidate with a nomination on a particular MOC's slate will compete with those on the slate. The notion of entry from the national pool is very iffy at best, now you are in a situation of competing for what ever slots remain open after the MOC's, Vice Presidential, Presidential, Prep, turnbacks, international student have taken slots in the class. This year, there appeared to be very few appointees given offers from this group. There will even be less next year. Any candidate stands a better chance competing within their MOC's slate.
Perspective: Even in the national pool, there had to be a few hundred appointees. If all reps and senators had 1 eligible vacancy, (Some have none, some have more than one, let's assume all had at least one). That would be 535 appointments. Throw another 100 (Maximum) for presidentials. Throw another 20 (Maximum) for ROTC. That's 655 appointments. Throw in the yearly average of 50 prior military and 10 turn backs; we're up to 715. And we can add another 35 to account for any other categories that had some vacancies, or just to play it safe. That's 750 appointments. So, at the very least, there was around 400 from the national pool. That is this year with the drop in appointments. (I'm rounding off a lot of numbers. Actual numbers aren't that important for my point.)
This is just information. Not taking any sides. There's a lot of good information being given. And FalconFamily, you are correct. Even if there were 400 national pool appointments, next year will probably be about 100 less. Around 300 appointments from the national pool.
This is why getting as many nominations as possible is so important. Whether there's 1050, 1175, 1260, or 1310 appointments given, approximately 750 of them are going to be from SLATES. And if some members of congress have 2-3 slots open, because of people graduating or dropping out, they may choose to fill ALL their vacant slots. Some choose to hold at least 1 slot per year. I.e. If you filled all 5 allotted slots in one year, you wouldn't be able to give nominations for 4 more years. (Well, you'd still give nominations, but none would be slated slots. They'd all go into the national pool). So, when they get an extra slot back, not from graduation but from someone quitting, they sometimes hold it for that time when they have more than 1 applicant who walks on water.
Remember: The MOC has a Constitutional Rights to CHOOSE who the academy is going to take from their slate. If that individual is qualified, and the MOC says this is my principal nominee and you WILL give him/her an appointment, the academy MUST do so. Honestly; about 80% of MOC's defer their responsibility to the academy and simply give them a list of 10 names and tells the academy to choose.
Point is: On average, there are 750 appointments that are against slates. Moc, Presidential, ROTC, etc... Every one of these slates you can get on, gives you a better chance for an appointment. Remember; that slate for your MOC, you're ONLY competing against others in your district and/or state. Once that slot on the slate has been selected, you are now competing NATIONALLY. With up to approximately 4800 other qualified individuals. Not that they are all qualified; and not that some individuals weren't on more than one slate. Just speaking hypothetically of the maximum potential national pool. I.e. 535 MOC's, X10 names on each slate. Equals 5350 nominees. Average another 500 presidentials, etc.. You get the picture. Wouldn't you rather increase your chances by getting one of the 3+ MOC appointments that guaranteed, and can ONLY be had by someone in your district and/or state.
Anyway; just wanted to spit out a perspective for the OP and others who are thinking that they only need 1 nomination. FWIW: It's very common for those who get a presidential or other military related nomination to believe they don't need another nomination. That presidential nomination doesn't pull any more weight than another nomination. It's simply a slate. And if you don't get one of the 100 Presidential appointments, then you are heading for the national pool like everyone else.
On a side note: Many military related nominated appointments such as the presidential, can occur much sooner than others. E.g. You can receive your presidential nomination right now in July, and receive an appointment in October. My son, and many others have done exactly that. In those cases, where you have the appointment in hand, there is obviously no reason to continue on with nominations from the other sources. You have the appointment. But realize, my son didn't wait until October and an appointment before applying for a nomination with our senators and rep. He did that also at this time of year. (July). It's just that after he received his early appointment, he was able to inform the MOC's that he no longer needed an appointment slated against a Wyoming slot. He had one against the presidential. Our state appreciates this, because we are very small in population, and it allows another Wyoming applicant to receive an appointment. But had my son not received an early appointment, he would have continued on with both senator's interviews and our representative. He also applied for VP.
So as others have said, apply to all you are authorized to apply to. Your #1 goal is to get one of those 750 guaranteed slated slots. If you get to the national pool, having a lot of nominations won't help you. Where it helps is in getting one of the initial 750 slots. Best of luck.... mike.....