Re: the boat scenario diagram - I knew you put that together quickly, so don't take my criticism personally - I just wanted to point out that even "pretty" diagrams can be misleading.
I drew what I understood the situation to be from the written description provided. Do you think the diagram conflicts with the text in any significant way? If so, how?
"Slightly slower" does not equal half as fast. The "squiggle" isn't really significant, but you told me to "please ignore it". Well, if I have to ignore that, then what else should I ignore? (I've heard that before from an IJ).
Eric, I'm not trying to niggle - I was just pointing out that just because Boat Scenario diagrams are pretty, doesn't mean they are 100% accurate.