Well, C&D or MT wouldn't care about being American when they judge these cars. They've bashed PLENTY of American cars in the '90s! Now, if they were sponsored by Ford, then it'd be a different story. But they're not.
It's just that the automotive press considers it blasphemy to consider ANY car better than a BMW M. Even in the above article, they didn't directly come out and say "the M3 is a lesser car than the Mustang 5.0"
I'd go and say that it is, though. Because it delivers, even though no one expects it to. The BMW is always at par with expectations.
Think of it this way:
You buy stock at Google, and you expect it to appreciate because... it's Google. But if you buy something like, "ABC Fruit company" for $2.50, and it soars to $100 a share, you'll s**t yourself. 
And, you'll be glad you didn't spend $350 a pop for Google.
