For sure. Don't be a dick is a pretty good strategy. However, I didn't get the impression that was his intent though: "I laughed along with her joke until, with a shock, we both realized that I was actually laughing at her actual plan".
Right. I was neither being "frank" nor intentionally laughing at her plan. She was smiling, and I thought she was kidding. I was smiling, and she apparently thought I was approving. Suddenly, we both realized we were wrong. Oops.
At that point, the damage was done. I tried to explain why her approach of changing N things simultaneously wasn't more efficient than changing N things sequentially because of the combinatorial explosion of interactions, but she wasn't technical enough to understand what I meant by that, which made her angrier, and when I suggested an approach that would give us a temporary "Plan B" just in case we "ended up a couple of weeks late", she declared me "unsupportive" and ended the meeting.