Wow Paul ... that must have been a lot of work (and moving forward as the working out the kinks phase begins). 

Congratulations!

Ang

Setting aside the letter of the rule for the moment, (which after all is as much about what is practical to enforce as anything else) and going back to the principle of "a boat shall compete by using only the wind and water to increase, maintain or decrease her speed", it seems to me that a single kinetic action to 'catch' an overtaking wave and sail down it for an extended period of time ought to be legitimate, no matter how big the wave or how much faster the boat goes on the wave. On the other hand an action that fails to catch a wave is dubious, and multiple failed attempts would be illegal propulsion. But how you would translate that into something a judge can enforce is quite another matter.

Thanks Ben ... yea .. you asked how the reasoning would go and I obliged :-)

I don't think this is quite right.  It is making a RRS 2 protest look like a RRS 69 hearing which it is not.

I agree that a breach of RRS 2 that affects the fairness of the competition on the water will usually be accompanied by a breach of Part 2, but even if it is not, a breach of sportsmanship that affects the fairness of the competition is nevertheless an incident in the racing area and requires a hail of 'protest' and if necessary display of a flag.

Agree, and in OP case, I think we have

Boat B broke RRS 2.  RRS 36(b) does not exempt a RRS 2 breach.  On valid protest B should be DNE.

A lot of chat for a rather simple case.

To me... there are 2 halves to OPs question...

1st half - was Red racing?  Yes.  Her stern was still on the finish line when she broke rule 10.

2nd half - Did Red tack and gybe in accordance with 44.2...namely 'promptly' after the incident? This question is subject to the protest system, just like any other allegation of a breach of a rule not exonerated.

So the RC registers her second crossing i.a.w. Finish (a), and if anyone (RC or another boat) is unhappy about it, they can protest her for not exonerating 'promptly'.  Otherwise her 2nd crossing finish stands.

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As for the r23.1 discussion, Racing is a time-block from time-a to time-b.  Once you pass time-b it's over.  You can't restart.  If Red had met the interpretation of Case 127, then she was past time-b.  Not racing.

If a boat not racing breaks a rule, then apply RRS 60.5(c)

If a boat has broken a rule when not racing, her penalty shall apply to the race sailed nearest in time to the incident.

What am I missing?