Rub, you are right, that the word "secret" is not completely true. This publication is free to get in the KH for study.
But,
Can a JW unbelieving husband (who does not go to the meeting) get one?
Can person aproached in a FS get one?
Can JWs friend, neighbour, workmate ask for one just to see?
Can any Bible-scholar get one just to check JW beliefs?
Official policy as presented in KH - NO WAY!
If I am not allowed to obtain some information, i consider the information as a secret. (I am sure you have some proper word for it in english....) But I dont want to argue over words.
Albert