I think you have a shearer issue. We have a flock of Zwartbles, when I took some skins to be tanned I was told that as they were Zwartbles they would cost a bit more due to Zwartbles having thicker skin than most breeds!! However we did have a problem one year with a shearer cutting along their throats but we haven't had him back, I think part of the problem might be that they are less fat than some breeds so maybe easier to catch the skin, but there shouldn't really be an excuse if the shearer is careful.