HOWEVER - I'd bet that F18 was anticipating the tack. They had no rights as the clear-astern boat on port. A hail from the F16 gives the F18 plenty of opportunity to keep clear as the F16 sails her proper course by tacking for the mark. The fact that the F16 made it to the mark first indicates to me that all is right with the universe - good job, Gill.
no, no , no. Once you start tacking you must keep clear and give other boats room to keep clear. You have started tacking once you go past head to wind. In this situation the F18 only has to "start" taking avoiding action once the F16 tack is complete, which is when the boat is pointing in the direction of a close-hauled course on the new tack. 1 boat length to windward and 5 astern isn't enough room in my opinion to complete a tack without the F18 having to start avoiding before you have completed the tack.
In this situation, the best thing to do tactically is to pinch early and climb above the F18 to make room for yourself to tack. Hopefully the F18 doesn't follow you up maintaining their tactical hold over you.
Rules wise though, if you don't want to continue too far past the layline, you are allowed to luff, due to proper course limitations, but tacking in this situation is asking for trouble.
