Skill rating 2 is generally considered "professional quality", whilst 3 is "noticeably above average" and 4 is "world class" - the sort of individual you'd expect to be famous (at least within their profession).
DM+1 is not unusual - most random characters have at least one DM+1 characteristic, so seeing a 9+ in someone's 'defining' characteristic is good but not unheard of.
DM+2 means a characteristic of 12+ EDU/12 - which puts them in the top few percentile of human achievement.
DM+3 is the most important thing here; because DM+3 means SOC15, the absolute maximum possible for a PC, which means the individual is basically a planetary duke/duchess. So (from a cynical point of view) they win legal matters by either being or having influence over those who have the authority to decide what the law is.
