Well, I haven't given my sermon on drag radials in a while, so here goes:
I don't care if you cut a 1.4 on DR's. The question is, what WOULD you have cut on a slick under the same conditions?
DR's are a big compromise relative to slicks. Especially on turbo cars, which are tricky to launch to begin with. A little too much boost and zing, DR's go away. Slicks, on the other hand, can take pretty much anything you can throw at 'em.
The only earthy reason I can see for running DR's at the track is if you're broke or lazy, and insist on not changing tires. That being the case, you'd better be prepared to lose, because 60's and consistency are out the window.
On the street, other than being expensive, out and out dangerous in wet conditions, wearing out within a few thousand miles (rendering them just as illegal as a slick), and picking up every pebble, every stone, every cigarette butt and subsequently sandblasting your quarter panels, they're just fine.
Let's face it. It's nice for the Mustang boys running 6's @ 200 to say they did it on their DOT legal tires they get for free and change every pass, but that's about as far as it goes.