not really sure about the wiper, but i would definately recomend dynamat. i think i spent almost an entire day dynamatting my truck when i did my system, and it really helped. You obviously don't have to go as crazy as i did, because i did my ENTIRE truck, undercarpet, headliner, etc. Either way, this should really help to cut down on vibrations, as well as road noise when your driving. Come to think of it, it might actually help the wiper too. Being that it would be sucking up vibration, it might also reduce the vibrations going to the wiper.
Good luck
Jim
Good luck
Jim