Daniel I disagree with that tbh every dog introduced right will not dig foxes and some of them just don't have it in them full stop and you can't put it into it either otherwise what would be the point of breeding a working terrier if any old thing of the street introduced right would work and tbh ....I've seen more dogs drawing look like superstars and not be worth a tap on top of the ground when it comes to lurchers each to there own but if I get a decent one at a fox and can run I wouldn't let it up a hole at heavy stuff it's all right them laying on up in there in control of the animal ha