I think something to keep in mind is the possible differentials from history. It might seem weird for me to say this, but the technology tree -- anything, really -- does not necessarily have to follow history. The reason is that Civilization V, or as I imagine the Call to Duty Project, is not supposed to be a recreation or simulation of history. It's supposed to be for you to play through historical eras, and, in doing so, it doesn't necessarily have to follow the specific timeline of actual history. It just needs to be logical and probable. For example, even from the historical point of view, the Wheel was not absolutely necessary for technological development, the Inca being absolute proof of that. However, it might also not have been necessary for Calendar to follow maybe Mysticism or something. It's not that I'm saying the whole system of technologies leading to other technologies should be revamped.
The alternatives would probably take more time than it's worth. However, in contrast to my usual rhetoric, I think that the focus should be more of necessary progression than historical progression. For example, you can't build a chariot without before having learned the wheel. That's just logic. At the same time, however, it is not absolutely necessary for writing to follow oral tradition. It's not that writing doesn't usually follow oral tradition, but there are also many differentials to consider as well. For example, some countries in Africa got oral tradition but never got writing. Writing didn't necessarily follow oral tradition for them.
My solution for that would be that maybe some technologies should be dependent upon the year than upon other technologies. It might even make the technology tree easier, because much of the difficulty laid in the historical arguments, and, as I said, history is a good reference for many things. Our human history provides a good reference for social policies, because our history has essentially given almost if not all of the possibilities of types of governments across all the civilizations that have existed. At the same time, however, there are so many differences across all civilizations over technological development that, you know, it can't really be generalized to reasonable accuracy for most things.
The alternatives would probably take more time than it's worth. However, in contrast to my usual rhetoric, I think that the focus should be more of necessary progression than historical progression. For example, you can't build a chariot without before having learned the wheel. That's just logic. At the same time, however, it is not absolutely necessary for writing to follow oral tradition. It's not that writing doesn't usually follow oral tradition, but there are also many differentials to consider as well. For example, some countries in Africa got oral tradition but never got writing. Writing didn't necessarily follow oral tradition for them.
My solution for that would be that maybe some technologies should be dependent upon the year than upon other technologies. It might even make the technology tree easier, because much of the difficulty laid in the historical arguments, and, as I said, history is a good reference for many things. Our human history provides a good reference for social policies, because our history has essentially given almost if not all of the possibilities of types of governments across all the civilizations that have existed. At the same time, however, there are so many differences across all civilizations over technological development that, you know, it can't really be generalized to reasonable accuracy for most things.
. And I agree with you (and with 3335d, who also agrees with you) that as long as the techs are logical, then historical accuracy is not as important. However, the idea that techs are dependent on year is not something that I can get behind. 
If civs are granted techs by the calendar, what is the point of having a science focused civ? Giving them after a certain amount of time equalizes the tech among all players, effectively taking out arguably the most important part of Civ5; the tech race.
which custom button?
but its getting there 
Found the evil text 
. It seems that whatever was causing the slow loading has now been fixed 
