I am really unsure why you think this is a contrary statement. I said Long Tails are NOT a disadvantage. However, in keeping with the thread:.Au contraire. Sometimes they get stuck and the very strong tail allows the owner to pull them out.
From the AKC breed standard on Scottish Terriers:
The tail should be about seven inches long and never cut.
http://www.akc.org/breeds/scottish_terrier/index.cfm
Ironically, the American Kennel Club, which is less than 150 years old, has some of the most antiquated standards. They still require tail docking on many breeds or they're ineligible for shows.
I believe the mandated docked tail or DQ was a rule in the past and if I remember right, it was changed in the late 70s. Again from the AKC standard:
http://www.akc.org/events/conformation/faqs.cfmEven if it is traditional in a particular breed that the dogs have one of these alterations, it has the same potential to win as any other dog of the breed and will only be judged based on the compliance of that dog to the breed standard.
I have to read the above as No natural tail (barring deformations) will be disqualified being as several breeds do DQ for docked tails.
http://www.akc.org/sitesearch/index.cfm?q=docked+and+disqualification&submitsearch=
I found no dog breed that has a DQ for undocked tails (or ears). I may have missed some.
Some breeds are penalized for undocked tails (poodle/boxer/etc) in the ring but again, this is simply the archaic mentality of SOME dog breeders, who also via that same mentality bred the brains out of some of the working/hunting dogs for coats and head shapes, introduced health issues via breeding for color and other aethestics and are not truely working for a better breed of dog.