Investment partnerships are the perfect breeding ground for "groupthink".

Despite the fact that the majority often rules, that does not mean the majority is always right.

The most poignant example comes from a premier venture capital firm I once worked for. One of the opportunities it gave its investment professionals was the chance to invest personally and on a discretionary basis in each round of each financing in which the firm participated. You did not have to invest, or you could invest the maximum, based on your level in…