As for the RC's error in not putting a spacer mark in. It helps to prevent these situations, but if it is windy, the Stb boat with the kite up will still be sailing down into the port boats tracks. If the sailing instructions say that there is no spaces, the competitors should be aware that this situation may occur and plan for it.
Indeed, if I'm faced with such a setup of bouys then I won't approach the weather mark anywhere near the port layline. I would tack through the middle or go to the starboard side of the course.
Wouter
