Well... it kind've depends on how much the song is promoted. If it is Momoko herself,that wouldn't really work because she most likely would not even mention the title .
But if it got TV promotion itself,billboards,and concert performances,maybe .
I honestly think Motto Zutto/ROCK Erotic was a smart move. Two TV performances,a tie in concert/event with Ju=Ju,quality MVs... I think that is the step they should take forst. Then as Berryz continues to succeed (If they even do), then throw in a billboard here and there,add some more events/TV promotion.
Simple. Start small. Go larger. They have to see what works for them though. Right now,no one knows