You don't need to share private keys or passwords to share a UID, each person can have his or her own public key in .ssh/authorized_keys Of course I agree that

You don't need to share private keys or passwords to share a UID, each person can have his or her own public key in .ssh/authorized_keys Of course I agree that this is still bad practice from an auditing perspective (and assuming a password is needed to su/sudo you do need to share that password).