Upvote:5
There's nothing secret on it. Instruction handbooks are distributed to those holding a calling that requires it. Handbook 1 mainly contains instructions for bishoprics and stake presidencies, while the handbook 2 contains instructions for the rest of the organizations of the church; it just happens to be the case that there's way more people holding callings included on the volume 2 (this is why it's more available).
None of the 2 volumes is "honor bound", the only thing they contain is a bunch of instructions and guidelines for those holding a calling that requires it.