I've really enjoyed these posts. Seeking wisdom from a crowd is very tricky. You have pointed out many of the shortfalls. I am interested in how the opinoin gathering from the crowd moves into decision making. Often you gather opinoins then need to make a decision. If it is a situation that is somewhat democratic, you will want consensus which will run the same risks you have laid out. You could effectively gather independent opinoins and the truth may lie in a minority opinoin that is overwhelmed by the majority in the decision making process.