So would I, Sean. In fact, I wrote a paragraph about that but deleted it for the sake of brevity, but I'll restate it: I do think that if hypothetically, rebirth were somehow proven false, I believe that I still would want to practice the dhamma, since regardless of what happens post-death, it is still certainly relevant to our present lives, which I tried to communicate when I said "The Dhamma would still be useful as a means for coping while alive". Maybe coping isn't the word everyone would prefer, but either way I agree about the utility of the dharma in this present existence. And I specifically picked the terms "necessity" and "must" to communicate that regardless of weather or not we -should- strive for release from dukkha, we don't -have- to, since that release will come regardless.
Also, note the bolded if in my post. What I meant to signify is that rebirth becomes more of an issue of consideration when one is not able to be awakened in this life, since if you are, then regardless this birth will be your last. But as hard as we might try, not all of us will accomplish that. I'm making no implications about your or anyone else's ability, I'm just saying that weather the potential is there or not, not everyone will be enlightened in this life, and even if you are going to be, not everyone else is, so when considering the well being of all, it becomes a larger issue than that.