In an interview with Variety at the 2018 Cannes Lions film festival, he revealed that the scene in season 5 when Stannis Baratheon allows Melisandre to burn his own daughter Shireen alive was a little too cruel for him.
“I thought [it] was just cruel. It made sense story wise and I understand why they did it. But I just couldn’t watch it. It was difficult to even read it.”