Finally, it helps you with strategies. How? Just like every other sport there are certain strategies teams or players may use to be a step in front of the opposing team. The simulators help players strategize by allowing the player to CHOOSE WHAT PLAY they want to run at what time and how to run it. For example, on 4th and 3 to go a RB may chose to RUN A POWER AND BOUNCE IT OUSTIDE to catch the defenders off guard. It may work or may not, depends how they run it in the game which will be transparent to what they think on the field. On 3rd and long a QB may chose a PASS PLAY and pass it to his best WR double guarded, over a wide open mediocre receiver. By doing this over and over the QB will learn to stradegize and give the defense a SHOULDER AND PUMP towards his best receiver and then turn and fling the ball to the mediocre one on the other side of the field for a 40yd gain.
The awareness, knowledge, and strategy all combine to improve the mentality of players.
http://commons.wikimedia.org/wiki/File%3ADerrick_Henry_All-American_BowlU.S. Army all-star bowl By Tim Hipps [Public domain], via Wikimedia Commons