Nah, Coke has significantly more "bite" (boy it's hard to come up with the right term to describe it) than Pepsi does. I don't think there's a significant difference in caffeine content between the two.

I'm honestly baffled that there are people who have trouble telling the two apart...

In Barq's vs. Mug -- quite true. Haven't had either in probably 10 years but Barq's "bite" is the caffeine.

It's not bitter, it's literally like dashing something from the spice cupboard on your tongue.

Only 22 mg of caffeine in a can of barqs. You sure that is what you are tasting?

Ever tasted raw caffeine? Yeah I am sure.