One of these dogs still looks like this. Is it a coincidence that the modern dogs that do not work do not look right? I do not think so!
The show ring pretender will tell you that "form is function," but that is bullshit mumbled by people whose own dogs have no function other than to chase ribbons.
In the world of the working terrier, the hole and the wild animal in the den pipe are the test.
And it's not just a test of the dog, is it? Here's a shovel.... start digging!
Theory crashes pretty quickly in the hedge.