A lot of busy, high-profile people (Noam Chomsky, for example) have done off-line AMAs. That is, commenters will post questions, and upvotes will determine the best/most popular ones. And then, answers for those will be posted all at once, maybe even as a different thread if enough time has passed since the questions were asked.
That would have been an excellent model to follow here, and probably would have meant more time spent answering each question (for the President) and higher quality questions getting upvoted (since there's plenty of time for the collaborative filtering process to shape the question-space).
Did you read the second half of the article? It's about how the author overcame his urge to blurt out the first compliment he could think of. He learned to dig deeper and find something about the person that's truly commendable.
It's pretty clear that this tutorial expects you to already have some experience with concepts in revision control. However, the problem is that if you're already experienced in revision control, you would probably find this tutorial a little simplistic and condescending.
Basically, git has a steep learning curve and people haven't found a good way to flatten it out a bit.