First of all, congratulations on getting it to swim. A four inch, three section bait is not an easy build. Can you post a pic, so we can see what we are discussing. Pics are allowed as long as you are not just showing off your bait and it is valid to the discussion.
I think that your biggest problem is mounting the hook in the second segment. Probably would have been much better to mount it in the first section. The head generates the water forces that push the second section and generate the S shaped wiggle. By mounting in the second section, you are effectively stifling the action. By mounting the hook in the nose, you will be damping the first section and more forces will be imparted on the second section. The result should be a steadier nose, a more fluid action and probably enough energy left to drive your dressed hook at the rear.
There is nothing you can do to improve this bait, other than check the hinge joints and make sure there are no rough spots. The slightest blemish will spoil the action. Try the nose mounted hook on the next build.
Edited by Vodkaman, 17 August 2011 - 10:07 AM.