I think that brought as a pup and brought up as you would a lurcher they would be smashing on all quarry. Think about it, a pure greyhound is as fast as you can get, its undiluted and pure. Whatever you put into it (collie, bull, bedlington etc etc) waters it down and detracts from the speed. The only way of not detracting from the speed is to x it with another pure running dog (whippet for accelaration, saluki for stamina).
A retired greyhound (ex track dog) only knows straight ahead and straight lines and not for very long at a time. Its body, muscles and bones have developed to be doin