Yeah, I find regular soda nasty after phasing it out entirely some ten years ago after realizing that I'd gained ten pounds from it. Never did actually get back to 150, although that was a bit scrawny anyway.I drink diet soda because I almost universally prefer the taste of the diet version - certainly do with Coke, I find the 'real' version has a nasty aftertaste.
And from a practical standpoint, I think it would be unwise to drink a dozen regular sodas a day, as I do with diet sodas and did with regular sodas as a teenager. That "two a week is moderate" line is hilarious. Twice a week is moderation for a heroin user, not an imbiber of a harmless beverage. Two sodas a week is for desert ascetics who sit on top of pillars and grow their beards to the ground.