I've been hog huntin since I was old enough to ride in the saddle with my dad and I'm 22 now and I've yet to see this but it is definitely believable with the way coyote populations are around the Setx area...
Loftin, I have had it happen a couple times in the past, once in nome texas and the other 2 were both in labelle texas on broussard land, I wouldn't be at all surprised if the coyotes in labelle were the same ones both times. I have read in the past that some guys think that once a coyote has figured out what the dogs are doing they will hang around for an easy meal. I don't know how much truth there is to it but I do know that both times it happened in labelle we gutted the hogs on the spot and the coyotes were on the pile before we were out of site, it was pretty cool. I kill em when I see em but for some reason I didn't see any need in it on them, can't blame em for takin advantage of an easy meal AND i'm not to worried about em messing with my dogs, they can hold their own pretty good. the momma to 2 of my up and comers still in her old age will run a coyote down and kill it given the chance, they are pretty rank lol.