I was looking through Rabbi Gil Student's blog, www.hirhurim.blogspot.com, and I came across an article from last November about the much-maligned Gosse theory discussed fleetingly on this blog about a month and a half ago. I read through not only Student's post but also all of the comments (quite a tedious task), then posted a comment of my own, because I felt that none of the comments had adequately addressed the questions being raised. As I acknowledged in my comment, it's very possible that no one will ever look at those comments and read mine, since it was posted many weeks after all the others. I'm posting it below in a different font, and maybe, this way, someone will read it. Maybe.
I assume nobody is even checking these comments any more, but I'll write something because I find this topic a good intellectual workout. Yitzchak is right that just about any objection one can possibly raise about the Gosse hypothesis can be addressed with a little bit of imagination. Albus Dumbledore could probably do almost all the tinkering Gosse theory requires God to have done; I imagine God could do it too.
As for the theological/philosophical issues: God doesn't make his existence or the truth of the Torah too obvious, because if the Torah were as clearly true as the link between jumping off a skyscraper and dying, people would not have enough free will when making a decision of whether to do right or wrong. It's important, theologically, for there to be some grounds for doubting (though not refuting) God's existence and the Torah's credibility. I personally believe that Rabbi Dr. Dovid Gottlieb of Ohr Somayach has put forward a persuasive rational argument in favour of the Torah's veracity ("Living Up to the Truth;" google it and you'll find it). For people who wish to take a rational approach to determining the truth, there need to be objections that they can raise, if they want to, to counter arguments like Rabbi Gottlieb's, and persuade themselves that the Torah is not true. God may thus have decided to create the world looking deceptively old (= Gosse) to provide an excuse, as there must be, to people wishing to shirk their responsibilities to God and religion (and to the truth).