A good Field Master is a blessing for any huntsman. The converse is equally true.
Have you ever wondered why your Field Master follows closely upon the huntsman and hounds at times, yet at other times keeps you further back than you, as a keen field member, would like? A good Field Master is always dancing between what he or she knows you want and what he/she knows the huntsman needs.
Good Field Masters ride well, of course, and are confident in their ability to jump whatever comes their way. They also need to be well mounted. I have seen many a good-riding Field Master made to look pretty poor because they were on horses that were simply not cut out to lead across country.