[Bramblecot]

  I suspect that a few breeders back in the bad old days did sneak the odd cross in as a pure bred animal, and this would show up once genetic testing does come in,
Dogs too.  A very experienced gun dog breeder once told me that every few years they 'chuck in a collie to pep up the Springers whatever the pedigree might say'.    Just take a really good look at some black/white Springers 

[PDO_Lamb]

Some shows have a young handler class and in my expirence youngsters are welcomed and encouraged by all.