What did Holmes add to watson's conclusions?where was Watson wrong?

This question has already been asked and answered. Watson believed that the walking stick was a gift to its bearer from a hunting club, Holmes concludes that Mortimer received the stick as a gift from a hospital because of its initials.  Watson believed the man was an older country doctor, Holmes disagrees and says he was a student, young, and had relocated to the country to open a practice. Holmes adds that Mortimer must be absent-minded, amiable, unambitious and a dog owner.