I have seen more and more people state that a breeding is Lean Mac free. What are some of the issues that tend to have people shy away from Lean Mac? It is pretty apparent that Lean Mac lines have produced over and over again. Is it traits or hereditary issues or something else? I am looking to get a new pup in the next 6 months any and all information would be good. Not intending to disrupt or hurt any breeders out there but just want to be informed as much as possible. PM me if you don't want to say it to everyone. Thanks.