The problem with using Boat Scenario is that the time scale is hard to get right between different tracks. This diagram illustrates that perfectly.
BoatScenario is by no means a perfect tool, but it is relatively simple to use and allows one to cobble-up these diagrams without too much fuss.
For example, between positions 1 and 2, blue moves almost two boat lengths, whereas yellow moves just a bit more than 1 - meaning that blue is moving twice as fast as yellow, even though yellow is sailing a lower course and should be going significantly faster.
The initial description said that the windward boat had overstood the layline but was sailing slower than the leeward boat. W was clear ahead at the zone, but later became overlapped, just as the diagram shows.
Also, the little S curve in blue's track between positions 4 and 5 is unrealistic - unless there was a current going from left to right.
Please pretend the little s-curve is a straight line. It is an artifact of how BoatScenario draws tracks, not an intentional representation of Blue's course. I tried to get the boat positions and headings right and didn't worry too much about the track lines.
Yes, the program is imperfect. Yes, it does introduce errata when animating. Yes, there are situations that BoatScenario simply won't draw (such as sailing by the lee). Nevertheless, if I had to resort to a less convenient tool (say, Corel Draw), I wouldn't have posted a drawing at all.
Regards,
Eric
