Estimates of underwriters' estimates are presumed to be indicative of management opinion. That's a touch shady to begin with, ideally the analysts shouldn't have any "extra" information in the first place, right? Given that a change in those estimates is interpreted as a change in management opinion -- if that change is communicated to one set of investors, the others are disadvantaged.

To me a lot of this falls within reasonable expectations of how openly subjective information can be communicated in the first place. Any communication involving judgment and ambiguity and anticipation is going to travel better and faster within some social network, and that's going to advantage some over others. I don't think the advantages are insurmountable, crowds are often wrong and anyone good at this stuff can find their way in. But I definitely see why other people find the whole thing fishy.