Sorry I dont understand your discustion here complet.
As the curent Target is Part and the next step would be group then why you are assuming this would only target 1/2 of a group?
I wondering because my Mage with Flexible Formulatic Magic have this spell.
Also what would happen if it is reduced to Individual as target because this would also be a posibility of this virtue.
Maybe only Circle would be the posible reduction in target so that the mage have to draw the circle first on the ground.