I don't think the Governor could really care less about the prison. He wants Andrea, maybe, because she reminds him of his wife. Eliminating her old group, and Michonne, would leave her with nowhere else to go, and she'll stay there with him. Merle is only interested in finding his brother, and by kidnapping Glenn & Maggie, to find him, he's gonna bring a shitstorm down on Woodbury. I predict something will happen to Penny, by Andrea, or someone else in Rick's group, and THAT will cause the Guv to go apeshit, and lead an assault against the prison out of pure REVENGE.
Totally agree. I think its unlikely he doesn't know where it is. I mean he plots to steal supplies from any outsiders he can, why wouldn't he have known about the prison, especially with it being so close and if he is actually from the are pre-ZA?
Also I think people are missing a little bit of the point of Woodbury. While the Gov takes every opportunity to strengthen the town the town Itself, Woodbury is about restoring a lifestyle of that before ZA. I agree a prison would be the safest place and practically impenetrable by a hoard, but its not conducive to a normal pre-ZA lifestyle that the Gov is trying to achieve. So its not so much about what makes the most sense safety wise, but what can assure the most normal but safe lifestyle possible.
I agree with the governor not wanting to give Andrea options, but I think it goes further than that. I don't think he wants to give anyone in Woodbury options. He wants everyone to buy into the Woodbury lifestyle, so he can be their messiah. Rick's group, the national guard men, and any group like them, provide options.
Also, I don't think the governor does know about the prison yet. I say that because the prison was still well stocked with supplies. If he did know about it, why didn't he liberate the supplies?