Comparing and contrasting Lovefoxxx and Karen O.

Am listening to the new, better-than-I-expected Yeah Yeah Yeahs LP (first single "Zero," which isn't nearly as good as some of the other tracks) and speculating as to how even better it would be if Lovefoxxx from Cansei De Ser Sexy were doing the singing, but I'm also remembering that I myself have thought that Cansei De Ser Sexy ("Rat" here) would be better if Lovefoxxx could actually sing rather than perpetually relying on a basic open-mouthed wonder-talk that as for embodying a tune can't do much more than wave at the melody. I mean, what if Lovefoxxx could keep a tune as well as Karen O. does?