I'm not expecting you to have the actual explanation on how it works, but if you think it factors in then it would only make sense to have at least some guess on how it may work. I fail to see any useful explanation of how OVR would practically be used in determining sims. Maybe this is because I have some experience programming simulations and understand why the Madden OVR would be a poor value to use in the type of simulation I believe is being run.
The point I'm trying to get at is that Overall ratings in Madden are 100% dependent variables and therefore have little to none utility in a complex simulation engine which has direct access to all of the independent variables. It would be a failing on the part of the developers if it were the case that OVR directly influenced the results of the simulation.