Buzz,
getting back to your original post... I too have noticed this obvious trait too often on various cars, and have wondered how it happened or why? Then looking at it a bit further like a piece of art... something else sort of popped out at me over time.
If you notice, on some of these cars that have the perky butt distinction, it might also be attributed to the ride height in the rear, or front to rear relationship, and wheel position within the rear wheel well; not just the shape or slope of the rear quarters only.
For example, if you take a Contemporary or an FFR, or even an SPF for that matter and jack up the rear a bit too much, and if the wheels stick out a bit, it accentuates it even more. Take that same car, - lower it down - and tuck in the rear wheels a bit by narrowing the rear, or using different offset wheels, and it sort of disappears. i.e. hence the famous squat seems to remedy the problem on some cars, and cures it on others. It's a fine line.
man I need to get off of this site, I can't believe I'm taking the time to type this... with better things to be doing at this moment. See Ya.
