so what about phantom eggsacs?
Those are not fertile eggs. I believe they're talking about fertilized eggs here. And yes, for eggs to be fertilized the sperm needs to go where the eggs are, which in this case is inside the female spider. That's basic biology.
i meant to say, tarantulas, can still lay eggs, even if infertile. I think i didnt undertstand the definition of english word: gravid. I thought it meant pregnant with eggs, unfertile or not.
You are correct - gravid means carrying eggs, but does not mean that the eggs are fertile. For the eggs to be fertilized, the male must insert his emboli into the female's epigastric furrow and deposit his sperm into the spermathecae. The female will release the sperm at the time she lays her eggs, thus introducing the male genetic material to the eggs for fertilization. If the male never made a successful insertion during pairing, then there is no way the eggs can be fertilized when she lays them. In this case, though, given the behavior of the female during successive pairing attempts, I would suspect that there was a successful insertion at some point.