The part you quote was not the only warning sign to stay away from the IPO. Just a quick search brought a whole page (published before IPO day) of reasons to stay away: http://www.zdnet.com/blog/feeds/facebook-ipo-risk-factors-an.... Regardless, big IPOs like Facebook are driven by hype, not sound financials. I'd be willing to bet that Facebook could have used 24 point type on their login page stating: "we're losing money hand over fist" and there would still be people lining up to pay $42/share when that bell rang.
Were insiders withholding information? I'm not going to argue one way or another. How do you "know what you're doing"? Start by knowing that insiders would stick it to their own grandmothers if they could get ten cents more per share. But when one's whole strategy is to hope for a first day "pop", that's playing a lottery ticket, not investing (exhibit: Zynga). For one, if one buys after the opening bell, you're not going to profit from the pop, you are the pop.
Were insiders withholding information? I'm not going to argue one way or another. How do you "know what you're doing"? Start by knowing that insiders would stick it to their own grandmothers if they could get ten cents more per share. But when one's whole strategy is to hope for a first day "pop", that's playing a lottery ticket, not investing (exhibit: Zynga). For one, if one buys after the opening bell, you're not going to profit from the pop, you are the pop.