In any given X-Wing match, your standard red attack die has a 50% chance of producing damage. Throw on Expertise, and suddenly, it rolls over to 75%, clearly making it into the 'Top' lists of EPT's around. Ironically enough, I penned this article in March, before Justin Phua put it on Dengar and subsequently won the 2017 Worlds.
People will initially find it too much of an investment at a cost of 4 points, matching the likes of the rarely seen Expose and Opportunist. However, it is this ability to nullify the need to take a focus action which makes it very difficult to apply a points cost on, and how much this effects the game play turn-to-turn.
This unlocks the potential use of other actions every turn, barrel rolling/boosting into a more favourable position, evading, or even target locking.
Han Solo - Expertise, Finn
Rey - Expertise, Finn
Norra - Expertise
Boba Fett - Expertise, Dengar
Dengar - K4 Security Droid
Of course, the major weakness of Expertise outside of the points cost is stress. As soon as that stress token lands, the 4 points becomes null and void for at least a turn. At that point, those 4 points are a temporary waste. Although having a wingman like Epsilon Leader in your squad would be great to mitigate this, it is a massive 19-point investment in order to trigger a card.
Playing effectively is the best way to mitigate this event. If you're facing off against a stress build with R3-A2, Tactician or Asajj Ventress to name a few, target accordingly.
If you're playing a game and you avoid any stress-inducing mechanics, then Expertise is an amazing investment. If you haven't already tried it in your squads, don't delay, replace your commonly-used EPT's like Predator and see how it changes your game play, especially in the long game.
Has Expertise changed the game for you? Do you know include a stress-giving mechanic to counter this in your squads?