I was wondering, has anybody really played around with the civ-specific tech trees?

Admittedly, I was a little dissapointed about how it works, but it works, and that's the important thing..

I was thinking about it though, and I realized that it could be extremely difficult to make very different tech trees for the various civilizations and/or culture groups. Because you will need to have certain techs be common among the different civilizations. I don't see a way that you could have the same technology land in two different tech trees... what happens if you give as a prerequisite two technologies that are each possessed by different civilizations? Will neither civ be able to research that technology since they will always be lacking the other tech, or does the game exclude the necessity of the unattainable tech and base it solely on the accessible tech? I would imagine that we would not be so fortunate and that it would be the former rather than the latter...

Has anybody played around with this new feature at all? And if so, have you found any cool techniques to get the most from the editor?