User blog comment:Zathronas/Analysis by an author: Volume 2 episode 11: No brakes/@comment-3146930-20141024021616/@comment-10380701-20141024024612

She had reserves during the Ursa battle.

She likely had reserves for this fight as well, it's just not efficient to pull out her semblance when it won't do much, since Neo is dancing around her attacks like it's nobody's business.

Her semblance makes her stronger, not faster, so it's not gonna do good.