Yeah, it took some digging to find this thread. The situation I'm in right now is that I have 5 letters of recommendation but my recruiter keeps telling me he'll only send 3 because no one looks at more than 3. And last time he sent off my packet he didn't include all 5 only the first 3.
Send 3. And send the 3 most impactful.
My most impactful letters were:
Former Supervisor- Gave me an outstanding letter saying I go above and beyond in my work, I'm extremely professional and reliable, have routinely worked outside my wheelhouse without complaints, and exceeded expectations even when the work wasn't expected of me.
O-4 (Known him for 15 years) - Great letter saying that I've been mature beyond my years since my teens, am extremely responsible, and that I'd be an invaluable addition to the Navy as an officer.
Former Colleague (Worked with and Known her for 6 years) - Great letter saying I'm dedicated to service to country, that I'm extremely responsible and professional, and that I'm perfect for service as a military officer.
A former law professor of mine sent one as well and it was solid, I just wouldn't put it as the most impactful.