I just re-listened to the episode of Destiny and Chicken by the @f-f-podcast ladies, where Bradley James was talking about the show, and he specifically mentioned how well Colin is able to make the audience feel absolutely everything his character is supposed to be feeling. He can rip your heart out and make you want to thank him for it.
No idea how he does that. I’d say it must be exhausting, but I remember reading an interview with the director of one of his indie films, and they were describing a scene where Colin’s character is just in DESPAIR. After the scene, the Director ran over to him, absolutely freaked out about whether he was okay, and he was like “Yup! Fine! Hey, are you all right?”