When I played through this, I decided to just go for it and never left the island, nor indeed did I send out any ships to explore. I actually managed to build the pyramids (researched masonry and started right away, pausing only to whip out temples and such) and settled great prophets/engineers eventually gave me pretty acceptable production. Sadly, when another civ finally discovered me in about the year 1800 I was predictably far inferior technologically. I'm not sure if this is really a winning strategy.