The offensive and defensive game plan screens have a seemingly subjective value that you will use to define the conditions for your play calling: Short, Medium, and Long. You may have seen this and wondered why you don't have the ability to specify specific distances ranges (you can, by the way, by setting up game plan rules). I wanted to take this opportunity to explain how this works and the ways you can control it.
The basis for this categorization is the idea that your team is going to adjust its play calling during the game based on how successful you are. The very generic description is that a "Medium" distance play is the distance that you would expect to achieve a first down if you used all downs available. So if you are expect to gain 4 yards per play, first and 12 would be classified as first and medium; second and 8 would be medium; and third and 4 would be medium as well. Short and long are used on the other sides of this logic.
The game begins where first and 5-15 is medium, second and 4-11 is medium, 3rd and 3-9 is medium, and 4th and 2-7 is medium. So, for example, 3rd and long would be 3rd and more than 9 yards to go. But, as the game progresses, if you are averaging more than 5 yards per play, your "short" distance will be lengthened, pushing your "medium"distance to a longer placement, as well as the "long" distance. Conversely, if you are averaging fewer than 5 yards per play it goes in the other direction.
Now, once you have played your first play you obviously don't want to consider that your average; if you throw an 80-yard touchdown on the first play of the game, you don't want the rest of the game to be stuck in the "short" distance category because it takes so long for that average to come back down. Instead of doing a pure average, your coaches will make the adjustment slowly. This is based on the "GP Distance Adjustment Speed" in your Misc Gameplan settings. The default is 5 - and we recommend you leave it there. You may set it to 0, which will completely disable any changes - leaving short, medium, and long constant throughout your entire game - which will give you more of the predictability you would expect from being able to specifically define these ranges. If you set it to 100, well, you'll get some craziness in your play calling. Using the default of 5, however, allows you to very slowly adjust your short, medium, and long ranges. Let's talk briefly about what this number actually means.
When the game begins, your "average" play distance starts at 5 yards, which as stated above, sets your very first play as a first and medium. Let's also assume that you have your adjustment speed set to the default of 5. If you immediately have a 10-yard gain, the new "average" play distance is 5% of the most recent play plus 95% of the previous "average" - 0.5 + 4.75 = 5.25. As you see, the "average" grows a small amount toward the most recent play without moving it significantly. If on the next play you gain another 10 yards, you'll grow a little more - 0.5 + 4.98 = 5.48. If you then take a sack for 20 yards, the "average" adjusts to 5.206 - 1 = 4.206. So, if you are moving the ball down the field well you will begin to use more short distance plays, and if you can't get the ball moving at all you'll start to inch into the long distance plays.
The defensive side of the ball reacts to the offense's decision for distance. So when your opponent calls a "short" distance play, your defense will also call a "short" distance play. So your defense technically is using your opponent's GP Distance Adjustment Speed, only because that is necessary to keep the tables even between the teams.
Hopefully this has cleared up some of the confusion regarding the gameplan distance and what the GP Distance Adjustment Speed means. As always, feel free to ask any questions in the comments here or in the help area of the community forums.