Well it's more about the "no discounts" thing than the "anti-Astros" thing. I never thought Boras was so much anti-Astro as he was "pro-squeezing every dime possible out of all negotiations".
I think HG is right, basically the only form of "hometown discount" Boras would allow would be in the form of a huge $$ per year shorter term deal. So no discount on the dollars per year, but slightly more palatable to the team in terms of not such a long term commitment. He (Boras) can sell that as still getting huge dollars, while saying Cole is betting on himself, because if he keeps pitching this well (or even close to it), a 2-3 year contract now and then a new 3-4 year contract after that would almost certainly be worth more than a single 6 year contract now. Give up the long term security in exchange for more overall money and flexibility, while expressing confidence in your client's abilities.
So anyway yeah, he's gone, and I will be sad about it when it happens, but this is all cart before the horse stuff, let's worry about winning the World Series this year before we worry about how they'll go about repeating next year.