The previous posters are right. The overall rating is weighted. Depending on how it is weighted, the overall rating will be different for two similarly attributed players. Here's the excerpt from OOTP9, which I am sure applies to OOTP X too.
AI Player Evaluation Options
These options control how the game's artificial intelligence evaluates players.
In OOTP 9, the computer considers both a player's ratings and his statistical performance over the past 3 years when evaluating players. By changing the values here, you can adjust the formula the computer uses to evaluate players.
In the example above, 30% of a player's evaluation will come from his ratings, 50% from his statistics in the current season, 15% from his statistics from last year, and 5% from two years ago.