Recruiter hold the keys to this option. Most applicants don't even know to ask about it. A classmate of my son's asked me to help him w/ his packet as he wasn't getting much help w/ the Recruiter. Asked Recruiter if he had considered him for Immediate Select Decision. He said no, that he thought the applicant was a "shoo-in" and sent his packet directly to the Board. Apparently once it goes to the Board, you cannot grant ISD. I was pissed when applicant did not make the cut nationally when he could have done so locally.
Pretty sure the reason he did not get selected was because he chose a "Tier 3" major and that greatly reduces the odds of getting picked up.
I am also not overly jazzed about the fact that NROTC Recruiting (at least in NRD Richmond, which includes the largest Navy installation in the world) is (or at least used to be) handled by a First Class Petty Officer.
While I'm on my soap box ranting, when it comes to the part where you get interviewed, be aware that you can determine (to some extent) who conducts that interview. It does not have to be the Recruiter.
It used to be that it had to be a recruiter, a commissioned officer (O-4 or above), or a retired officer (May have my stats wrong here). If you know an officer, I would highly encourage you to go that route. I think it sends a stronger signal if an officer tells the Board an applicant has officer-like qualities than if an enlisted does. Ask the Recruiter if you can get interviewed by an officer and then pick one that knows you. Chances are the officer will know you better than the Recruiter (who has to manage many, many applicants) does. Recruiter shouldn't push back. After all, it's to his advantage to get you selected.
Would be interested in Wink's take on this.