I sure want to know about this myself. We are planning to start our small chicken hobby 8-10 hens-  next spring and don't want any roosters either.  My husband is a veterinarian so it would be like any operation on a pet w/ anesthesia, sterile technique, sutures etc....still a risky procedure due to the placement of the testes in the animal....nestled right by two major blood vessels up behind the ribs.
 
Makes me sick anyone does this without anesthesia! ugh!
 
Truthfully has anyone known an adult capon....from what I have read they are caponized for larger weight gain then processed at about 20 wks.  We need to find someone with an adult rooster in this situation.
 
Please let us know what you find out.  It will certainly help us!
Thanks so much for starting this thread too!
Steph