A while back an MGoUser put together an analysis of downs and success rates. IIRC, the philosophy was that you needed to gain 50% of the yards needed on the down for it to be successful, except on 3rd down, where you needed to convert. In an article that Brian linked under mgo.licio.us on our defense, the author talks about how successful Indiana was on 1st and 2nd down, and that was the main reason for Indiana's high 3rd down success rate (58%). Just a note, Indiana came into the game converting 41% against basically 3 FCS teams.
My request is that for a little help from the MGoCommunity in answering the question of, "How successful was Indiana moving the ball against us based on the philosophy outlined above?"
If the original author reads this, can you please confirm the philosophy or correct it if it's wrong?