Line/family breeding is proven, look at the lads that have the best kennels of terriers and ones that continually produce good dogs and a high percentage of good workers and they'll say the same.
Thinking that breeding to unrelated blood will bring better results is sheer ignorance IMO.
Foxdropper from that it seems you've bred from head bangers and produced head bangers. A lot of kennel fights and losing dogs because of them would tell me there's something wrong within the blood, we have terriers not pit bulls, IMO dog aggression between kennel mates is a bad fault and must be a ball ache to be scared to turn your back on them?
I apologise if I've read it wrong but that's the way it has come across.
Seems odd how no one on here has heard of them, the dog world is a small world an everybody knows somebody. Hope you get the result you're searching for...
Well find another printer! Cracking drawing, I'm sure you'd sell plenty if you got more done, even as a second edition so not to upset people that bought the first edition.
They're a good idea for your own piece of mind, but I think regular exercise is enough for an 'earth dog'. After all when pitbulls used to be fought they were both equally conditioned to the optimum etc but how many foxes run on treadmills? That's my view anyway.
I know a few that are out at this time of year and then again late summer, but come the cold, hard winter months you don't hear off them. Fine weather hunters, not just terrier lads either, plenty of lurcher lads the same.