I appreciate your feedback! :) It's difficult to convey mental state over a single line of text, giving rise to various interpretations that weren't in the intent. Imagine I am your best friend and I say the same in a playful fashion - would that be more acceptable?

Absolutely! That's actually in the hacker news commenting guidelines: "Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith." https://news.ycombinator.com/newsguidelines.html

So to answer you question, yes, it would be more acceptable if you were saying that to me in person. In fact, I agree with you about the flow of the lectures, and I was looking for someone to bring that up and I'm glad that it's getting discussed here.

However, Jeremy and Rachel are both reading these comments and we should strive to provide thoughtful, fleshed out feedback. The work they've done on Fast.ai is a tremendous lift, and deserves more than a drive-by comment.