I didn't see it linked, so here's the Stack Overflow thread that documents some of these sqlite3 hacks for enabling access for assistive devices programmatically.
http://stackoverflow.com/questions/17693408/enable-access-fo...
I love the first comment on the question:
> No, there is no way to circumvent the need for visiting this screen. It is one of the operating system's base protections. Any way that is found to circumvent this will almost certainly be patched out. – Jul 17 '13