ClayJar:Other than the card, I don't think I need it, although I will of course glean every speck of new information the course may provide.
My reasons for wanting the card are plentiful: Flower Gardens (at least one charter there), Pennyroyal, Haigh, Gilboa, White Star (officially, at least... don't tell on me :biggrin, et cetera. It is the means by which many sites choose to limit their perceived liability, and if I want to dive solo at their facilities, they require I have the card.
(I truly love learning, but in this case, that's basically lagniappe -- I'm seeking the card primarily for the access it grants.)
I'm surprised Gilboa lets you dive solo period, card or not.