While I have no doubt your brilliant nephew would kick my butt I would still play with him.
Last night my daughter and two granddaughters showed up to play games. The oldest granddaughter is currently obsessed with phase 10 so that is what they wanted to play. I am not a fan of card games. But I played. Half way through I got a call from work. One of our people was giving staff a hard time and the staff wanted me to come talk to her and calm her down. So I was gone for an hour or so. When I came home I learned my younger granddaughter had played for me and I came in second lol. She told me when I got home that I played much better when I wasn't around! lol very true statement.
I had told them that if I played phase 10 someone had to play scrabble with me later. But.. they left when I got back home.. and I have still played no scrabble : (