Good points there blackstaff. I think alot depends on percentage of bull. Bull blood might increase strength and bone but it would reduce speed, and i think if you get a good whippet they can take a hell of a bashing. As for better feet they would be heavier dogs so probabaly more prone to foot injury. A thought of mine was that you would be adding more terrier blood into the whippet blood, so might up the chances of yapper maybe?? just a thought. Good point about the stamina though
like chunk said whippets been tried and tested for years.
not trying to contredict evrything you sai