Bucky Brooks of NFL.com has a rundown of the Chiefs secondary and what they're trying to do in 2010 with Romeo Crennel at the helm. Most of the article is the standard stuff we see quite often these days but he does have an interesting nugget regarding Crennel's tendencies with the secondary.
Known for using a clever blend of coverage and pressures, Crennel's system is deeply rooted in a "quarter-quarter-half" cover scheme that has the ability to suffocate offenses if executed properly.
The field is split into quarters with the strong corner (typically the left corner because most offenses tilt right) and the strong safety each responsible for covering a quarter of the field. On the weak-side, the boundary corner and free safety play a half-field coverage to create a double team on the split end (X-receiver). With the corner playing a "cloud" technique (corner is aligned three-to-five yards off the receiver forcing an inside release on all routes to ensure that the safety is able to stay on top of the receiver down the field) to disrupt the release of the receiver, the scheme can make it difficult for the quarterback to find open receivers.
Very interesting. The Chiefs will need the secondary to play very well because the pass rush isn't anything to write home about. Usually it's the pass rush that helps the secondary but it may be the other way around in Kansas City.