Vaulnerabilities in a Defense

Vaulnerabilities in a Defense:

An over-aggressive defense is vaulnerable to trap running, angle blocking and draw plays.

A weak defensive front is vaulnerable to trap running, and zone (hat on hat) blocking. Against a weak front, you can lead more with your fullback as the D-line will not penetrate the O-line.

A slow defensive front is valnuerable to outside running, tosses, reverses, and sweeps. This is what the Saints would like to do with Reggie Bush. Get him to the outside. This is also why Emmitt Smith never ran outside, while Barry Sanders was forced to sprint for the sidelines. Less power upfront means more outside running and off tackle stuff, while strong lines simply knock people off the line and run up the middle.

Against a poor tackling defense, you may choose to isolate CBs and Safties by letting them run free at the running back thinking that they will miss a tackle, i.e., John Riggins against McNeil in the Super Bowl. Poor tackling is like having an extra blocker on the field.

Need visual proof? Watch this play on YouTube. A defender is actually allowed into the backfield to miss a tackle so that the more important players don't get penetration.
http://www.youtube.com/watch?v=J8cexwNdeyQ
P.S. you cannot simulate this action with any touch tackling.