First - this is a short video of how I prefer to move pigs between paddocks. It takes a bit of time to set up, but I mow a path, then set up a section of electronet on each side (not charged). The pigs then follow me (and a bucket of food) without wandering too far off course. Makes for simpler trouble free moves.
Very nice hog drive. I opened up a new paddock for my hogs and they have yet to move into it. Two of the three will cross the line, but the other one gets up to the line where the fence was and stops. The two wire electric fence works, even when its not there anymore!
I am going to make the fence more visible so its more of a contrast between there and not there. I have only had them in a paddock situation for about three weeks now, and we are still figuring it out, .
They are very visual creatures, and also very space oriented. Your problem of them not crossing where the fence used to be even though it's gone is a common one. Give them a visual queue perpendicular to the old fence line that is new and different and that helps them register that it's ok to cross. Once one or two come through the rest are more willing to follow. If you notice in the video I was considering just waiting them out but I said 'that'll take forever' then I bent down the grass and got one of the smaller pigs to follow enough to cross the line which kicked off the rest of them.
We ended up with a few outside the perimeter of the new paddock - their herd instinct is strong enough that those managed to jump or go under the fence on their own to get with the others. Your results may vary, so don't rely on that
Part of it is also definitely training - the first few times they move are harder, but it gets easier. I've had groups of pigs bunch up in non-existant corners unwilling to cross an imaginary line before. I've also experimented with turning the fence off - my berkshires would go for a week with it off and still respect it, the ossabaws don't take nearly as long.