Interestingly my personal taste-testing anecdote in this thread started because I stated that I could distinguish between American Coke and Mexican Coke (given that one is corn syrup and one is cane sugar) which led to the challenge to even be able to identify Coke over Pepsi.

Might still be, that one wouldn't be able to distinguish corn syrup Coke from corn syrup Pepsi. And similar for a comparison between the sugared versions.