I don't understand where's the "46" in the play (46 normal weak blitz) http://plays.myfootballnow.com/307.png. For me, it's a "43". May this wrong "tagging" explain that the play is called in the wrong situations, hence its dismal results? In "real" football, 46 is against heavy passing, right? Or am I missing it completely and the play is really a "46"? Why then? Thanks.

The plays tagged as "46" basically mean that all but one safety are lining up within 5 yards of the LOS. I believe the idea in the '85 Bears' scheme was that the pressure from all those blitzers made it impossible to develop your passing game against, so plays from that formation are typically heavy blitzing. It is interesting, if you get a chance, to watch the '85 season Super Bowl between the Bears and the Patriots (I recently watched this game on NFL Game Rewind) - we are used to seeing offenses with quicker passes today because teams had to adjust to the 46-style defense, and it's almost comical to watch the Patriots have no answer to it, as most teams today would probably have a better strategy to overcome it than they did that day.

My point in saying that is yes, the 46 defense was built to go against the pass, but it was less about coverage and more about QB pressure. So it's a good package if you are wanting to get into the backfield quickly, but will also expose your secondary if the QB hot reads to a quick pass.

BTW, you are technically correct in your comment that it is a 4-3, I just have it labeled as a 46 because it's the alignment that the Bears primarily used in their 46 defense.

The "46" defense was named after Doug Plank, the Bears safety, who wore #46........

Thanks to both! It's very informative and useful.