Well, blocks are part of the game. I don't see how it complicates anything or why you wouldn't use them. I play a wizard and I use blocks all the time whether or not I think they're going to hit me hard...in fact they're my main way to defend because my athletics tends to be lower than my spell-casting skills.
Besides, I think I gave perfectly valid, narrative reasons to use physical blocks to block incite emotion.
You need to see your target to hit. Vampires don't have any supernatural senses to detect their prey. Narratively, a veil or a block on line-of-sight could make an incite less effective. So while it's not specifically under a veil, narratively, it prevents a vampire from zoning in on you and hitting you hard.
And that's not even considering that, if they don't have the ranged upgrade, you could argue that you could use athletics to dodge (since they have to touch you). And, By that argument, any old magical block would do the trick.
So, I don't think it's outside the realm of possibility to say that you can use the meta-physical form of the element to protect you from a meta-physical attack.
Edit: I get the feeling that you feel it's too OP to use SPellcasting to block incite emotion. Remember, they have to, either, dedicate an item to defense, or spend an action blocking. Either way, they still get their natural discipline to "dodge". I don't see the problem letting them use an action to do that.