I also have a hog problem and my goal when fencing my land will be to keep them out. From what I've seen on other peoples land, hogs and coyotes will dig under a woven wire fence to get in. It doesn't take much for them to get enough under it to get through. Some people lay down predator fencing flat on the ground, outside their fence and hog clip it together to stop the digging. I'm told it's very effective, but then the coyotes learn to climb the fence. Not all of them, but there are some that will.
My current plan is to install my fence about six inches off of the ground and then run a hot wire between the fence and the ground. I've had VERY GOOD results at stopping coyotes and hogs with electric fencing. I think that once a coyote gets zapped, it loses interest in what's behind the fence. Works on racoons too!!! Hogs hate electricity more then any other animal. They are super sensitive to it!!!
Another bonus to this plan is that I can spray round up and not worry about the salts rusting out the fence. Being off of the ground should extend the life of the fence significantly.
I will spend the extra money for the most powerful charger that I can get. My current one is rated for 2 joules and sends out electricity in burst, which allows it to deal with wet grass or a branch falling on it and grounding it out. I'm also thinking about connecting my ground wires to the fence itself and using the T posts to act as ground rods. While they are not deep enough to be ideal, they will help with maxing out the zap the animals get out far away from the charger. I will also ad multiple copper coated ground rods to the fence to make sure I'm getting the strongest zap possible. I will also use the thickest, heaviest gauge wire for this. Off the top of my head, I believe 12 gauge is the thickest available.
I'm really tired of dealing with wild hogs. I'm bored shooting them, and would just as soon never see another one!!!