Researching early neuter/spay?

I'm currently doing research into the early spay/neuter topic. I am starting out as a Registered breeder. i registered in January 2010, I currently only have a stud dog, but plan to own a ***** in the future and have puppies within the next 5 years. I am involved in conformation showing working with a local breeder that has over 45 years experience. I have observed matings, whelpings and everything else involved from mating to finding homes. The thing that concerns me is, in my time as a registered kennel, I have had numerous enquiried from people who would love a puppy, but will become backyard breeders. I love my breed and reccommend it to everyone and think they should experience them if they suit their lifestyle. So I have been trying to find opinions and such on spaying/neutering pet home puppies before they are placed at 10-12 weeks. I have been shocked and disgusted at some of the suggestions and enquiries I have had from people in regards to breeding. One lady asked me to put my dog over her 7 month old cross bred *****, which is completely rediculous, but she later found someone that would put their dog over her. Lots of people in my opinion can't be trusted even when a rebate is offered upon proof of desexing. I have played with the idea of not transferring ownership of the puppy on the papers until this proof is provided, but then who is to say they wont breed without the papers. I can't police that... Opinions would be appreciated, but keep it pleasant. (re-submitted for more exposure)