It would also be very interesting if he could get his hands on coke from different markets as the formulation varies from country to country. One of the most obvious is the amount of cinnamon, but it would be very interesting to know if more differences were there.
Another interrogation of mine would be if, sugar aside, the formula is different between regular coke and coke zero. I'd bet is is, simply to offset the aftertaste that aspartam/artificial sweeteners have, but I'm curious if other non-sweetness related ingredients do change.