Heroes 5.5 WarGame Edition - Tactical Edition.

Tried it: indeed, the Secret Crystal, Wall of Swords, and Hive spells became free!
So, there's no room for mercy!

In other words, am I understanding the situation correctly: if a hero has the "Dark Replenishment" skill, these spells are cast for free (and 20% faster), regardless of anything (whether or not the opponent has resistance to them)?
Is the problem only with these spells?