Doesnt castrating the hobs take the agression away from them like with dogs.
It prevents most sexual aggression but it makes no difference at all to their working ability.
I have hobs on my team but I do prefer jills for places where digging is not possible. That being said, in the places where it is then the hobs certainly get the job done!
DOES IT STOP THEM FROM KILLING AS MUCH. AS I WOULD DIG UPTO 3FT FOR A FERRET