I have absolutely no idea what the two digit score represents.. to me the dude that got a 99 makes me think of Gretzky.
When we interview people, we get a sheet with what the candidate's three digit score is, and how that compares to the national average overall and in G-surg. If the step I score is great, then we're not generally interested in step II (unless its a huge drop- so if you did well on step 1, I would blow off step 2 'till after interviews).
If the step I score is not hot, but the step 2 is great, then we'll take the better score.
If step I is not hot, and step II is worse... major red flag... not prohibitive... but you got some 'splainin to do.
To echo Socialist's tirade... you can score a 260 on the exam but if you come off as an arrogant jackass in the interview (or at the social event) and rub someone the wrong way (interviewer, secretary, resisdent's SO you talked to) enjoy your residency somewhere else. I have watched it happen.