I've been using the addin cognito from digitalcarversguild.com to drive the position of a unicycle along a tight rope in both the X and Z directions and also driving the wheel rotation with a cam providing a wobble effect . So in effect the whole performance can be controlled by moving the keypoints for jusat one attribute.

The fall is separately animated using a motion path and some rotations with lots of groups to stop the interactions of motions.

Link to movement without the morph.
http://www.thefleafilm.co.uk/VideoGallery.php?Vid=R23fY8hXBec

Thanks to some earlier assistance from Renderosity also have a rope with a couple of morphs in place that allow it to bend in the right manner.

I was wondering if the Driven tweener from associatedfx.com could be linked to the motor in Cognito so that I don't have to hand animate the bending and more importantly I don't have to keep fixing things if I choose to change the pacing. I did try an experiment but could not get it to work.

http://www.sparrowhawke3d.com/  

Try the free Wheels Modifier plugin from sparrowhawke.

I have looked at the wheels modifier for a different part of the project i.e. the ambulance that rescues my poor fleas. It's ok for co-ordinating sets of wheels and steering the vehicle along a path.

However I don't think it will be able to drive the movement of the morphing rope.