Pitbull Castration - A remedy for ferociousness?

Some of the pitbull owners think pitbull castration is a perfect remedy for ferociousness. Even some owners fear to have their pitbulls castrated because they believe it will cause them to get fat. Here I am enumerating the advantages of Pitbull castration-

1. Stops unwanted pregnancies
2. Completely stops urine spraying and marking
3. Agression towards other male dog will be completely stopped.
4. Minimizes the roaming in the street, which in turn minimizes the accident and decreases emergency hospital visits.
5. Decreases the incidence of life threatening diseases like prostate cancer and prostatitis.

As bottom line, I would like to confirm that your pitbull agression will be minimized if it is castrated. The surgery will not serve to make him more passive if your pitbull does not have an aggression problem.