Seems like it is worth a try. Basically it extends the z-threaded rod so that you can use the entire rod instead of losing that last bit to the support structure of the y-z sandwich. The only problem will be if it is not perfectly straight and cylindrical as that would cause z-wobble. Looks like a pretty easy change to make and then put back to original if it doesn't work. BTW, this wouldn't work on my PBjunior as the limit on that printer is the smooth rods, not the threaded rod.

Cheers,

KDog