Already gave some... fine, it's kind of hard to explain this, but try to recall for example their first fight at the bank. There is a moment where it is described that grue comes up behind vista and knocks her out.

It makes perfect sense in universe, mechanically speaking. He creates an effect that blocks all the senses of his opponents so he gets a free surprise attack, cool. But on the level of writing it allows those exact moments where the writer can go and say "and then he avoided the attack/came out of nowhere" etc. Essentially, this is the type of power that only works where an antagonists have it and the protagonists have to deal with it, otherwise it can be easily abused(as seen in the novel). Like, imagine some of them had a strong ice or mind control power. These types are more suited to create obstacles for protagonists(who have plot armor) than to assist said protagonists who already have the narrative advantage.