Basic duck milking has been covered elsewhere.
Likewise there are related quotes such as: "Son, one day you'll become a doctor or a lawyer or a duck-milker. You'll be looked up to. You'll be respected."
There is even a delightful TIME article from 1932 masquerading as a 21st century web page that helpfully defines the slang "go milk a duck" as an "expression of annoyance" widely used at Vanderbilt.
There is even the stray intriguing photo that is perhaps related to ducks and milk. Admitedly the duck in this case is a nurse.
As for advanced duck milking?
That's a different story.
Now I may not have used "duck milking" during the Depression at Vanderbilt and I might not have thought to set up a password protected web page at Tripod on the topic of duck milking but yes, To Blind Eve returns zero results for advanced duck milking - then again the blogsphere is flat (it's more of a blogoflat, think help I'm stuck on the long tail and can't get off) so who knows maybe I'm just pretending not to be a Vanderbilt graduate with a Tripod account?
Regardless here goes, advanced duck milking - make sure the duck isn't rabid.