Or is this just a new modification for the sake of modification. Seems the free moving head kills the action of the blade. If it didn't have the paddle tail trailer would this design impart any action on the bait from the blade?

http://www.bassmaster.com/gear/gear-review-z-man-chatterbait-freedom

Stanley jigs has had something along them lines for the past 3 years. Personally I do not like it. I have found that the fish slapping at it will not get hooked. The fish needs to bite and turn on it to get a good hook set. Lonnie's "hell razor" can be fished like no other. I like stroking it off the bottom. This is more of a jig bite in thick cover.

I got a few for free so I decided to check them out. . .doesn't make sense to me either. I don't like the way it looks in the water with the trailers I use and it does slightly reduce the vibration. . .which is the whole point of the lure. Plus is it really easier to change hooks when you just want to rig a new trailer? WTF?

I didn't like them and I didn't get a bite on the two I tried - I tied on a standard 3/8opz z man chatterbait after I tested the freedom and I caught 4 fish in roughly the same stretch of water. That was all I needed to see.

I gave the 4 I had to a kid at the lake the other day.

My guess: freely moving heads are currently selling well ex: Biffle hardheads and Gambler wrecking ball

Agree; part of the greatness of bladed swimjigs is the resulting action on the skirt and trailer. The freely moving head would significantly reduce that minimizing any theoretical benefit of less leverage for the bass to throw it.