You do what you do Charles and it's kick-* each time. We need someone in the trenches and behind enemy lines on our behalf, launching questions and counter-examples at strategic moments during your discussions for catch-22's and implementation/archetectural details.
The last thing which I remembered just now is that Greg always had this habit of checking his time, and not just "what time is it" time, but the "omg i need to go faster or ill never finish" time.
I don't know if thats just something specific to his character or some other reason, but he might have a more passionate explination of content if he wasn't stressing out on trying to keep the lecture on good caidance.
Just wanted to bring this to his attention, as it is noticable and might be pulling him off his refined professor groove a little.