[ While he might not always pick up on the more subtle things? This was different. He can feel that relief and gratitude, even if it's never spoken aloud.

Even amidst these unfortunate circumstances, he's just glad to see Moriarty's doing okay for the most part. Heck, he's even getting to learn more things! What a great day this was! ]

That would definitely explain why it's hard to master, now that you mention it.

[ Both hands clapped together and suddenly he seemed to be a bit more energetic now. ]

Oh! Moriarty!! You'll never guess what happened!