I received an email recently from a member on Vimeo that his Lumix 12-35 mm F2.8 lens had a stability problem even when the image stabilization was off while shooting on a tripod. Here's a link to his video.
I decided to test my lens to see if it had the same problem. My lens has the 1.1 firmware. The following video is the test that I conducted with my GH3 and my GH2, plus a test of the Lumix 35-100.