I did that mod too FWIW.(Glad i did,best bang for time spent IMO)
My rear wiper prob clears 85-90% of the glass, and i'm ok with that. Seems like my car is a dirt/crud magnet with the back glass,so a rear wiper is a good thing in my case, just wish it did not use up SO much washer fluid during a cycle(most ends up down the tailgate panel )
Plus the wiper gets dirty also, and that might affect cleaning ability.

I tend to go thru wiper inserts pretty quick on my vehicles(and happen to use Rain-X on everything i drive )so i'll prob be in the market for wipers fairly soon (prob spring) Think i saw a thread somewhere about getting a certain Anco insert(part # unknown at this time ) and cutting it in half ,for the rear wiper.

 

Mod? What did you use?

 

If you're asking about what solman and 08black did to mod the wiper, check here........

http://www.socalhhr.citymax.com/hhrrearwiper.html

 

Oh..I see..thought he meant he changed the sweep distance to clean most of the glass..I'd be interested in making the wiper cover almost 180deg instead of the approx 120 deg....