If people are stupid enough to make non trivial investments based on trolls posting rather than doing some due diligence, digging and doxing, its their problem and no amount of warning is going to prevent them from losing their money on this or the next scam. Seriously, unregistered company represented by anonymous poster with dubious reputation and casino links in his signature doing PR? The person collecting the money has no public identity, profile or anything? Should be enough reason for anyone sane to think twice, even if they had a credible story, which they had not.
while I agree that people should research their investments, the problem is that new people have no way of telling who is a troll and who is not. Mabsark's argument seems very logical, and if you go through his post history, you see a lot of math that checks out and looks very legitimate. At closer inspection, he makes a lot of assumptions and misleads people, but someone who is not familiar with the security would not know that.
So, I think it is reasonable to warn against the FanBoy/Pumpers/Trolls.
Advice from a random person on a thread on the internet is certainly no substitute for critical thinking.