Got to say I haven't read the thread, but have kept lots of pigs of different sorts over about 20 years, and have never had any of mine castrated, and never had a prob. I think onece or twice I have even had boars and gilts together and still all fine.
The last couple of couples got pretty big - hams around 16/18 lb+ - both pairs were boars and I didnt have any problems.
I also kept all my ram lambs entire, and ran them with the complete flock, and as long as they were not killed in the "season" all seemed fine, perhaps a little stronger but nothing objectionable
All the best
Sue