I used to believe this also, it could not be farther than the truth. I changed my mind about this when I started fishing deeper water,structure and what not. I have caught many more bass, and Larger fish with a jig, and a plastic stuck to it, than I every caught on any free falling bait.
* There are times when free fall is better, but for the most part when fishing deeper water the jig and t rig out fishes it
Of course I agree with that, it would take all day for a soft plastic bait to fall weightless in water 10 feet deep or better. But for less than that it is a deadly technique. When it gets past ten feet I also like a jig or weight of some kind. The only rule I follow about fishing is, "there are no rules".