I had a problem with the wipers on my 2.5 RS Impreza. The wiper bushings were worn causing the driver's wiper to hit the A pillar. Solution here:
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's someone else's idea, not mine. I glued the new bushings into the wiper arms, put wire ties around them, then glued the wire ties to the bushings. That should last for some time, I hope. The bushing kits are available on Amazon or Ebay.