Hold a straight line - what does it mean? Can I use this phrase to say what's a person like? For example I'd like to say that this man always talks about people what he thinks about them, just in their face and doesn't care about any consequences, he doesn't give much thought to the fact that he can hurt smb's feelings or humiliate one or something. He holds a straight line about giving his opinion of people around. Is it acceptable or I've thought of sort of bull?