Wow, I am honestly not sure how people can read those rules and think that the chariot gets no impact hits at all.
Page 71 is saying that if the chariot is charged (ie the Chariot did not charge anything, but was itself charged) it gets no impact hits. It's an introduction to what impact hits are is telling us what they are, and that to get them you have to be charging. You don't get them on the first turn of every combat, only if you charge. OK, deep breath....
So...... what happens when a chariot is charged AND is also charging in the same combat on the same turn? If the rules on page 71 were the only rules about impact hits and combats where both sides may count as charging, I would agree RAW would tell you the chariot gets no impact hits. It's still a good bit of rules lawyering though, since honestly, if you read the whole text and realize what the rules are saying you will see they are telling you that impact hits apply when a chariot is charging. That sentence about impact hits having no effect was NOT written in regards to a unit charging a charging chariot.
Now, even if you can't grasp that, and still think that a chariot should get no impact hits....
We have page 58 which states that when that happens (multiple units from both sides having charged into the same combat) all units count as charging and get whatever bonuses that implies. They specifically mention impact hits! How is that not clear?
The only way you can come to the conclusion that the chariot gets no impact hits at all is by ignoring the rules on page 58. Ironic since those that are trying to say impact hits are completely negated keep saying it's RAW. it's only RAW (and barely) if you ignore half the rules about the topic.
Sheesh.