It details how Age of Empires decided to make the game deterministic, how this had significant benefits, and how it's extremely difficult to do:
> At first take it might seem that getting two pieces of identical code to run the same should be fairly easy and straightforward -- not so. The Microsoft product manager, Tim Znamenacek, told Mark early on, "In every project, there is one stubborn bug that goes all the way to the wire -- I think out-of-sync is going to be it." He was right. The difficulty with finding out-of-sync errors is that very subtle differences would multiply over time. A deer slightly out of alignment when the random map was created would forage slightly differently -- and minutes later a villager would path a tiny bit off, or miss with his spear and take home no meat.
Do you think you look good by announcing that, since you don't know the subject you're discussing, you're not going to trust someone who does?