It has a feeling of being designed by committee, doesn't it? My utterly uninformed guess is that there were two factions in CA: one wanted to have a long game that covered from 1066 to the conquest of the New World; while one wanted to have people get quickly from the start to the end so they could experience lots of different units. But the only way to do that with characters that didn't die in a few turns was what they did.

It's kind of strange, and I thought I would hate it, but I'm pretty used to just counting in turns now and not paying any attention to what "year" it is.