This doesn't make any sense! There is no "comfort zone" for these shocks, they will provide the same amount of damping no matter where they start in the travel. I don't see how it could change the wear, other then maybe making it worse due to a smaller sideload moment on the piston.
If you shorten the shock rod, all you will be doing is deleting rebound travel, you won't gain anything. If you shorten the shock can, then you will overtravel the shock and smash the piston into the bottom of the tube.