It seems that as with most Revisionist Historians, Terry Jones has camped himself too far away from the well-established, traditional view of Roman history; and in the process has given the impression that he is just being controversial for the sake of being controversial.
I admit he does a brilliant job of emphasising the sheer volume of Rome's grasping nature, as well as the barbarity and violence within Roman culture, even if it was judged by today's standards...
However, he goes against the well-established idea that the violence within the Celtic way of life was probably on a par with Rome. Instead the celts are depicted as saints enriched with civilization and culture, living within an almost Utopian society full of equal rights and technology. Like Virgil said earlier in the post just because they made roads out of planks does not mean that they are comparable to the builders of the pyramids...I suppose I'm exaggerating my point a bit, but you get the idea.
Sure, the Romans were blood thirsty, but so were the Celts, so was everybody at this time. My point being that just because a civilisation is downtrodden and demonised by another, it doesn't mean that they are free of sin. I think it's a very British thing to love and admire the losers of History.
Though this may sound like an unfavourable view of Terry's series, despite his overall conclusion, I actually enjoyed the program: he walked into the past at a different angle...and isn't that what history is all about.