I don't think its any harder to get rid of either. Most of it has to do with the admin and documentation, etc. Lazy or incompetant admin makes it as much difficult as anything else.
Thanks. I know that in my experience with poor performers, following established procedures and taking the needed steps in turn almost always produced the desired results, even when an employee union was involved. The union representatives seemed very aware of the problem employees and were generally cooperative during the process. They seemed more concerned about strictly following the established procedures than anything else.