Habermas’ idea of intersubjective agreement establishes the idea that triangulation of subjective views between individuals to achieve consensus is a preferred method of achieving an equivalent construct of validity within his theory of communicative action. This is in contrast to instrumental action that aims at control over the natural environment, isolating variables and observing the effect on other unfixed but measured variables (the scientific method). In this domain of enquiry practitioners aim to limit the interference of subjectivity on the ability to clearly see the experimental effect of one variable on another. On the other hand, communicative action aims to negotiate consensus, thus encouraging enquiry and triangulation of individual viewpoints. Because of this, communicative action is a process that may be confounded by power hierarchies and political agendas. Communicative action assumes that participants who engage in dialogue seek truth at the expense of personal or political gain and this can be a problematic assumption to make in modern enquiry, whereby there could be a monopoly on being perceived as ‘the expert’. Those perceived as experts assume a higher level of authority and control over the dominant narrative. Therefore, the seeking of truth may be perceived (albeit implicitly) as less important than winning the debate and establishing or maintaining perceived authority. As such, there are problems inherent in the rather idealistic notion of communicative action that are so difficult to manage that it kind of renders the approach impossible to manifest in the real world. Bias exists and where dominating the narrative is the currency for authority, it is difficult to achieve a politically or power neutral negotiation of consensus, particularly in a world dominated by instrumental action and reasoning that values control and objectivity over subjective reasoning and the inter-subjective negotiation of consensus.
Perhaps thematic synthesis can act as a surrogate method to negotiate consensus between experts, ascertaining the convergence between expert opinions. If transparent reporting is adhered to then in my opinion this could offer the most power-neutral way of seeking consensus between expert authors. It overcomes the limitations of influence and power-play in conversation/debate that can be a dominating factor on the resulting consensus.