Who said it was a foregone conclusion? It's not a "non-negotiable" policy as far as I'm concerned. I am seriously interested if someone can produce a really good argument that we should not fork all at once. But I haven't seen any such argument. I think the strongest argument along those lines, so far, is that Wikipedia just doesn't have enough good content, period. But then, that would establish that we shouldn't call ourselves a fork of WP at all... Anyway, I'm not persuaded of the premise there.
In making any such summary, please look at my comments here: http://textop.org/smf/index.php?topic=45.msg355#msg355