DePaulo, Ansfield and Bell questioned IDT: "We can find the 'why' question in Buller and Burgoon's synthesis. There is no intriguing riddle or puzzle that needs to be solved, and no central explanatory mechanism is ever described." Although they praised Buller and Burgoon's 18 propositions as a comprehensive description of the timeline of deceptive interactions, they said the propositions lacked the interconnectedness and predictive power of a unifying theory. DePaulo "et al." criticized IDT for failing to distinguish between interactive communication (which emphasizes the situational and contextual aspects of communicative exchanges) from interpersonal communication, which emphasizes exchanges in which the sender and receiver make psychological predictions about the other's behavior based on specific prior knowledge; this conceptual ambiguity limited IDT's explanatory power.