I got Kevin Smith laughing hysterically on stage once without even trying, I felt like I'd unlocked some life achievement, it was awesome. I can only imagine how great it would be to get a laugh out of a legend like Terry Jones!
I vaguely remember Dan Harmon talking about this on his podcast, lord knows which episode. Basically about how his audience or random people he brings up on stage can spontaneously cause him to crack up more than any professional.
He reasoned that since he's a professional, when he watches another comedian act, he pretty much knows what's going on under the hood. He can predict where a joke is going because there are tried and true formulas, he can see through their pacing, etc. But if a noob cracks one, even if it's a joke he's heard before, he knows there's probably none of the calculation that a pro puts into it. It was a genuine thing, which makes it all the more hilarious to him.
Python was very much a group effort, but I think he made an enormous difference behind the scenes.