One thing to consider about v4.5 is it was set up to confine offenses/GMs like v4.6 currently does, however, we figured out the go-to plays.
Best way to put it is the following. You have a game vs. the actual AI - non-human and you are in the 'Scout Defense' screen. You're going to look at plays in which 1-2 of the top 10 will provide you with any ability to attack a red bar play. The rest will be zone and they'll be all the mostly utilized plays. What does this mean? You're looking down the barrel of a 1-game sort leading with Man Flat Zone (10-15 times) followed by that Nickel Cover 2 Man Under (10-15 times) and we can go from there.
Therefore, if you just run an FL Hitch infrequently and/or not make an effort to mash through the all zone AI alignment you won't win or move the ball.
Quick blanket explanation.