Well in the context of this scenario, it means that the leeward, right of way boat, must have a thorough understanding of the handling limitations of the windward, give-way boat. If she does not, then she must expect that any alteration of course could cause the give way boat to have to act in a non-seamanlike manner.

Not saying you're wrong (clearly, you are most certainly right), just that the interpretations that you've cited effectively put serious limitations on the the right-of-way boat. The windward boat doesn't have to anticipate that the leeward boat will try to luff her, yet the leeward boat has to anticipate that her luffing could cause the windward boat to capsize- hence the leeward boat has virtually no defense against a boat passing to windward. Something about that doesn't seem right to me.

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