I... that's a confusing question, because if you DID accept the premise of responsibility not being a zero-sum game, I'm not sure how you'd see anything about the other three points that required address. Those data points only work to provide the conclusion you've come to -- "criminal culpability being lessened" -- in a Responsibility-As-Zero-Sum system; otherwise, they do not equate to that understanding of what transpired.

However, I'm going to attempt to guess what you want addressed, though, and at least try to say something worthwhile about it. Here goes:

As I do not see responsibility as a zero-sum game, then I do not see any of the examples you posted as instances where the perpetrator automatically and inevitably becomes less responsible for the situation as the victim becomes more. Rather, I think the examples you posted show systems in which each person involved in the crime had their own individual levels of responsibility determined separately, with the rulings and consequences following from that understanding making sense in that context.

In more detail:

- Under your understanding of responsibility, there is a set amount of blame -- 100% -- and it can only shift from one person to another. Assuming only two people (rapist and victim) are involved, then if we say that the victim is at least 10% responsible for the occurrence of the event due to poor choices like inebriation and such, then the rapist's percentage of responsibility automatically gets reduced to only 90%... even if the victim were completely unconscious and the rapist drop-dead sober. Your understanding of blame is black-and-white thinking; an "or" clause: EITHER the rapist is 100% guilty and the victim perfectly innocent no matter what she might have done up to that point, OR the victim is partly to blame and the perpetrator is at least partially innocent. This line of thinking is often taken by newer-wave feminists and social justice warriors, and in the context of principle actually serves well, despite being pragmatically broken.

- Under my understanding of responsibility - the non-zero variety - there is not a set amount of blame, and every participant -- even bystanders and society itself -- can have a varying degree of it. Further, those combined degrees do not have to equal 100% (in total OR per-participant). Under this paradigm, the perpetrator could be determined to be 100% responsible for the rape -- undoubtably, definitely at fault, no questions asked -- AND the victim could be determined to have %20 of a hand in her own demise (again, given previously discussed factors). AND the people who watched or knew what was happening and could have stopped it but didn't have some degree of responsibility, AND some societal structures such as sports culture and/or the collegiate greek system could have a few percentage points... and, and and. This type of thinking, I think, serves to paint a more faithful, in-color picture of reality, social structure, and rape... and I find is often taken up by judges, well-selected juries, pragmatists, and people who view the issue as a criminal one, despite being broken and even considered insulting in the context of principle and social justice.

I think the outcomes of the points you raised make far more sense, and are even logical and understandable on a human level, when viewed through the lens of a non-zero-sum system of responsibility. Of COURSE there is a difference in opinion and action taken when something like blinding inebriation is involved; I just disagree that it means what you think it does.

Is that what you wanted me to address, or did I miss what you wanted entirely?