Hmmmm.... I'm woried about that too, it's a risky play....
Though
I can also agree that the mystery factor can be incredibly useful. If they just showed the new members at the announcement date, excepting the possible Kenshuusei ones, the rest, fresh new and almost absolutely unknown girls would give such a natural mystery atraction just by itself. Like they could really have some hidden supertalents....
Don't know if I'm explaining myself well @_@
Anyway, don't know if it's been like that with every audition but man, this is wooooooooahhhh!