By the times the romans were taking over the known world, charriots were seriously out of fashion as far as war went. I read some where that that they were quite effective in transporting 2-3 warriors in the battlefield quickly from one place to another by the "brits", but don't quote me on that.

I suspect that this low-tech. aspect is what they might have tried to simulate here by making the chariots so absolutely sh*te.