I think it might be a healthier to call rationality "systematized and IQ-controlled winning". I'm generally very unimpressed by the rationality skills of the 155 IQ computer programmer with eight failed startups under his belt, who quits and goes to work at Google after that, when compared to the similarly-status-motivated 110IQ person who figures out how to get a high paying job at a car dealership. The former probably writes better LessWrong posts, but the latter seems to be using their faculties in a much more reasonable way.
Not if most VCs lose money and are led astray by auctioneer's fallacy. Also not if a tertiary goal of most VCposting is to get people to quit their jobs and try, and so increase the supply of investment opportunities available to pick from.
2RHollerith
Yeah, but even if the advice VCs give to people in general is worthless, it remains the case that (like Viliam said) once the VC has invested, its interests are aligned with the interests of any founder whose utility function grows linearly with money. And VCs usually advise the startups they've invested in to try for a huge exit (typically an IPO).