Unlikely, at least i have not seen it used very often. countermagic once in a blue moon, shield never. The choice is always the character or the sword, and character wins every time.
For a Fireblade. The best tactic for Fireblade is the one I first seen in the Cradle scenario where the second rankers cast Fireblade on the spears of the Yelmalio templars int he first row.