Depends on if it is way off on the hard side or way off on the soft side. Between your ass (assume seat is soild, assume no chassis/swing-arm flex and looking at rear suspension alone) and the pavement, there are only two temporal energy absorbsion device; shock spring and tire spring; make one of them solid and the other will have to do all the work. The problem is, in addition to simply handle all the energy, the rear suspension and the tire are designed to do two very different things.