Some assumptions seem little more than convenient fabrications. Capitalizing a couple of words does little to validate the argument.
I wasn't using caps to claim the argument was legitimate. I appropriately used it to emphasize the word most important to understanding my comment. SHE became a Jew, She became a JEW, and She BECAME a Jew all mean subtly different things. When we speak out loud, it is second nature to show emphasis by upping the volume and changing the pitch in a word. It's a little tougher to do that in print, but one way is to use caps.
Just when did this happen, and with what Torah?
I had to take a day to think over just how to respond to this. I most commonly use the word "convert" in these kind of forums because it is the best approximation, one that others can understand. But I think the reality is something a little different. I think that Judaism preserves an older way of seeing the world, where religion is not something that is picked apart from the rest of one's culture.
My guess is that what typically happened back then is that when someone intermarried, one or the other person simply assimilated the culture of their spouse. The ENTIRE culture. The religious assumptions and practices were simply part of that. This would be especially true if the community in which they lived were a single culture.
It's why the word "conversion" is problematic when translating Geirut. For the sake of lurkers, someone who undergoes "conversion to Judaism" isn't just adopting a new religion. They are assimilating into a new People. They don't just study Torah. Being a Jew isn't just the heavy lifting stuff. It's also the enjoyable little things. Converts learn who Hershel is, how to bake challah, adopt yiddish phrases, shmooze at the Jewish community center, put Israeli flags on their walls.
So when I try to explain to someone that Zeporah became a Jew, it is more an appeal to my understanding that she left the people of her birth, and attached herself to her husband's people. With that came all of those kinds of things, both light and heavy.
And, as always, I'm fine if you disagree. I'm very much aware that I'm not really qualified to insist "These are the facts." I'm simply sharing my view.