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Braun and Sider (2007) argued that a semantic theory of vagueness is not committed to calling into question bivalence. They allegedly propose a semantic theory of vagueness which adopts bivalence and which accounts for our use of vague sentences. My main target is to point out the weakness of their theory. First of all, it is important to note that in order to grant bivalence they are ready to assume that most (if not all) natural language sentences do not express a proposition which is either true or false. As Braun and Sider are ready to admit, a consequence of this crucial assumption is that their theory itself is not true; even though they do not consider it a shortcoming, I will claim that, contrary to their contention, this is hard to swallow. Second, and more importantly, one of the main advantages they advocate for their theory is that it accounts for our use of vague sentences. As a matter of fact, the theory yields undesirable predictions as to how we react to vague sentences and I will argue that they do not overcome the difficulty.