Well, IW has already plenty of champions and high sellers for some people to be willing to use him. No doubt he will be used again and again on at least some of the cows that have already produced something special out of him. And some of that offspring - yes, including some of the good ones, are clean. No doubt some are trying to produce clean IW offspring the right way - by using him on tested clean cows, and testing the calves and sending the carriers to slaughter. I respect what those breeders are doing, but for my part if I want those genetics, I'll get 'em from the ones we already know are clean. But there's also no doubt there'll be others out there using it, just closing their eyes and crossing their fingers and hoping it'll work (if they even bother to do that). The question is, does marketing semen to the ones that are "doing it the right way" justify the use of it by those who don't?
As DL said, not using carrier bulls is the most logical and realistic way to eventually get rid of the problem. I think we're already seeing (at least in the Maine and Shorthorn breeding cattle, maybe not so much yet on the clubbie side) that most all of the new bulls being promoted are clean, and the few that aren't really aren't being well received. I think the same thing goes for bulls being sold for herdsires. I think though, that the carrier bulls that are already out there are going to have to run their course. I know their popularity is already declining, but they're gonna be around awhile longer.
I'm still arguing against PHA carrier cattle having a particular phenotype, aside from the coincedence that most of the carriers we're now familiar with are "showring friendly". Again, I think the idea that they do is dangerous from a couple of different aspects. If people truely believe they are phenotypically superior, then many people will continue to use them regardless of the consequences. Even worse, there are people who are convinced that they can identify carriers on sight, so they don't think testing is necesarry.