OK, sorry for the thread hijack BTW...and understood hailing "hold your course" is no longer in the rules,
If on a collision course (as P boat) and my intention is NOT exercise my option to tack, with S hailing "STARBOARD" to the last second, and guessing if I'll lee bow him?
And at the point when I'm obviously not lee bowing? (because it takes ~4 seconds to initiate and complete the lee bow tack) and still in collision course, then what?
Is he going to keep driving forward? thinking if I hit him I'll be DSQ'd and him exonerated?
I think instinctively S is going to do everything but blow his main sheet, or head up in to irons (he wants to maintain his speed).
At a critical point he may (or may not) do "something" to avoid contact by P which would likely be ducking P (and then protest)
Trouble is, that critical point would be about the same time I(P) would be starting a duck of him (S).

Given in the previous example, P is testing to see if she can get S to bite on a slight change in course in exchange for no lee bow.

What's the proper way to intentionally duck S? (when on a collision course) do I hail "I'm gonna duck" What? "ducking you" What?
Seems like "Hold your course" gets me nothing, rights wise, but it does clearly get my intentions across, legal or not?
Since my PROPER COURSE as P, in this situation is to duck S, (when not choosing to tack) do I just wave? give the OK sign?
Are you saying hailing my intentions is dangerous?
Enlighten me.

BTW, is asking "Cross or Tack?" a specific rule?