Someone on the pimms-pages forum did manage to bond a large group of boars; she seemed to find it much easier so introduce further pigs once the groups had reached some critical size. I guess that at some point the new pigs think 'this must be the bachelor herd' instead of 'a potential rival! drive him away!'.
Unfortunately the pimms-pages forum died a while back, and I don't think the old messages are still there.
I do remember that she introduced all her most mellow boars first, and that it took quite a long time, and a lot of planning. I guess that it will only work if you have a sufficient number of mellow boars that you have reached critical mass before you have to start introducing the more dominant ones.
That's the only time I've heard of it being done, though. It may be that she was just lucky. Most people stick to twos and threes.
