L1/L2 divergence, Part 5

Ever since he's become interested in World of Warcraft, J has been less active with Minecraft. One consequence is that he's not been watching as many "Let's play" videos, which provide exposure to rapid-paced colloquial language. When he does, he's been mostly choosing English-language ones, which has gotten me worried that it's becoming an effort for him to watch German videos for reasons having to do with L1/L2 divergence. 

However, this morning (and in the last couple of days in fact) he chose to watch German videos again: 

Later this morning I asked him about comparative understanding. He's generally quite reluctant to answer such questions and doesn't give what I would call rich responses, but he said that he understands the German videos still about as well as the English-language ones. Maybe that's true, maybe it isn't; he obviously senses my investment in his German-speaking ability and may be telling me what he thinks I want to hear. Still, it's something. He chose to watch the videos, after all, and had a lot to say about them.