The phrase "security through obscurity" is a term of art that is defined such that secrecy of private key material does not count. By definition, you are incor

The phrase "security through obscurity" is a term of art that is defined such that secrecy of private key material does not count. By definition, you are incorrect. Now, if your security relies upon the attacker not knowing your encryption scheme, then yes. That is security through obscurity.