I posted not long after I started hunting with the same problem. The advice I got was to shoo the dogs away, get after them just enough to get them off and keep them off of the hog and it worked. I have one dog that has been rolling out after his first 20 or so hogs. Another pup I started a few months after him started doing it even sooner. Last night they caught a small pig in a creek and we sent a cd just to be sure it stayed caught. When we stuck the pig all I had to do was say "caught hog, get ahead!" and they were gone on the rest of the hogs. It can make for some long nights, especially when 3 dogs roll out on 3 different hogs and are all bayed 3 miles away from each other!
I live for hunts like that!
