Stupid question, but since Google is a public company couldn't you lock in a certain profit on your RSUs with options in a private account? Or are you talking about the restrictions on vesting are meant to make them worthless for most employees because they'll be forfeited on some draconian technicality before exercising?
I remember on Bogleheads people talking about how to reduce the risk of investing in something like an ESPP to avoid an Enron scenario, and the consensus was using options in a private account so that you get a definite payoff.