Snort - I'm working that image..
but no. I've actually not known that many terriers personally.
I remember an airedale protecting a house on ocean front walk, venice, in the seventies, from the porch. (There were porches there then, before a lot of renovation syncopy.)
There were some leaping jack russells on our main street in my last home town.
There is Sally Dog, Diane and Dys', surely part terrier, loved by a2kers who have met her, including by Pacco dog, who, after an initial sequence of snarlphobics, just gave up and loved her.
So, my main thought re terriers, is insistence.