RE: Your caution is misplaced ! Well there is no safe guard against fraud, period.
Look at Sino Forest recently, and a bigger fraud still, look at Enron a few years back. That was the fraud of the century. When you falsify business records and the auditors are either in on it, or kept in the dark, investors are doomed. The investor public is vulnerable.
You can only make investment decisions based on the published numbers and records, which you have to assume to be accurate and trust worthy, no amount of DD is going to save you - experts or otherwise. It's just our bad luck that we were in on this investment and got trapped at the end.
Of course hindsight is always perfect. I often wish I could have gone back in time to November 14 and sold all my PSN on that day at about $13+. However, in investing you just have to move on, there is no "should have, could have, would have" in this game. If you keep thinking about that you should go back to investing in GICs. LOL.