One thing I learned in the Navy, was that ANY planning meeting that attempted consensus without open debate and open notation of final opinion is phony. Moderators start by telling you what you will be allowed to discuss, when you will be allowed questions, and state that the consensus opinion will be reported "later"; is an invitation to walk out, or even better expose them for what they are doing in a calm voice.
OK, then let me re-phrase: it has the capability of being an "above board" technique for examining positions and arriving at the good position PROVIDED that the facilitator/coordinator/whatever-to-call-him is HIMSELF above board. It's weakness is the ease with which the facilitator can rig the results. As Stalin noted: "Who votes doesn't count, it's who gets to count the votes".
In the Leftist Delphi Technique, essentially the facilitator is trying to give the impression that the participants are engaging in a fair and unbiased process, while the process itself is as rigged as a Chicago election. This leads the participants to accept the results, or at least not fight the results. The technique is as old as politics: isolate the opponents and make each think he's in a minority