That's the way many of us played it, but if his timing sucks as much as he's making it out to, and his goal is to be P-8 driver then being an absolute company man is the probably safest way for him to him to have the biggest shot.
He'll figure out how well he likes the VPenis once he gets into the fleet and sees how the sausage is made. He can make his decision on how he wants to play things after his first 6 months or so.
Unless shockingly he goes to a good squadron that has solid DHs and front office that mentors and helps them get where they want to go in the Navy and make personal goals happen. I concur with keeping some of your cards close to your chest but you should definitely try and not burn any bridges. One of the only ways you are going to learn about career options is asking questions and hopefully solid mentorship. My peer group has had quite the ballistic spread of guys and gals going different routes and success. Test pilots. Command of VP, VTs. Transitioned to FAO, HR and Intel. And of course those that got out of the Navy and went on to the civilian side. I have friends working their way up corporate America and regional managers and VOs with ATT, medical companies, Gulf Stream and of course the bubbas like me that went to the majors.
I've seen a lot of my peers change their life and personal goals over the years. It's not a good or bad thing but I think it is important to keep those doors open and options available to you. The best way to do that is be a professional and play well with others. Peers and superiors will try and help, but if you're an asshat, then not so much.
The other thread on work hours also has some bearing here. You really need to strive for a work life balance. Might be hard during those phases in flight school, upgrading, and deployments but having a way to decompress and outlet is key. Don't miss out on life, kids growing up, or enjoying your personal hobbies. Qualify early, fly a great plane well and you will do just fine.