Yes, definitely! It absolutely has an effect! The beauty of it is that because of this, Dark Elves can't use the "Chain Lightning + Armageddon" tactic! :p

What kind of "beauty" is that? The meaning of Chain Lightning's resistance to spells becomes completely unclear. And what's the point of Armageddon constantly appearing in the wizard's tower for warlocks then? After all, this isn't the second Heroes game, where you could actually only recruit Chain Lightning units and defeat everyone with Armageddon... dragons have already become much weaker, and further diminishing their main "feature" makes them completely unappealing...
The balance is suffering, in short.