Very good point. Milwaukee and Cincinatti improved this season. Clearly, St. Louis and Houston were considerably more talented than the rest of the division the past couple of years. Not so in 2006.
The Cardinals had a record of 52-29 within the division in 2005. Just 39-42 this season. 13 games!
It's basic math but it never ceases to amaze me that, after 162 games, 15-20 games are the difference between a great team and a mediocre team. I'm certain that you and I could look at our teams this season and easily find 15-20 games that they could have, or even should have won instead of lost. The little things really do matter.