"dirty little secret" generally implies something underhanded, nefarious, and treacherous to me. I don't think I've learned anything about that here on GCA.com, per se.
As with any craft or area of business practice, I guess we all know intuitively that some of those sort of things go on.
As to tricky and redundant design/build techniques, or 'overbuilding' a golf course beyond the course's market... well again, I suspect that to be the case sometimes from trying to read between the lines of some of the posts, but couldn't speak authoritatively on the matter.
Actually, I tend to think that I've learned more about the quality side of GCA, and the level of pride and professionalism that is present in GCA and associated fields, because we tend to have the archies, supers, principles and other people associated with the business of golf who care enough to come on GCA.com to explain their values and ideals and approches to their practice. The learning over the years isn't about 'dirty stuff' so much as respected practices and efforts that go unnoticed by the golf public at large.