OK, This is how I understand it. First bit; if you are clear ahead at the 2 boat lengths you can stear your course to make a seaman like rounding and go out wide and come in tight, afterall you are clear ahead, no overlap exists and so you have no proper course (per se) for the other boat to complain about (however in fact you do have a proper course (in your mind) as this is the quickest way to the next mark is out wide and in tight). End of story (well nearly, see however below.

Part 2, if someone clear astern at the two boat circle then comes inside they they are in the death zone and have no rights what-so-ever; well almost.. I don't believe that you could sail them into a steel marker bouy and cause them massive damage; you would have to give them room to "make their mistake" and then protest them; however if there was NO chance of damage occuring (i.e. if the mark is an inflatable) I would feel that you could just head up (giving them time to avoid you) and push them into the mark (and thus turn(s)).


THe crux of the second bit IMO is that you cannot allow them to crash and cause damage by their own stupidity; however you can push them onto a mark - One would hope that in the latter example they would choose to hit the inflatable mark instead of your boat. The defence of "well you left me room" is no defence.


However (there is always a however), assuming that they don't try and come inside you and duck your transoms (and so accelerate) they will probably come underneath you and are now allowed to assume (and expect) that you make a seaman like rounding and get onto a beat PDQ, you cannot sail below your course and they can push you up to close hauled.