This system, with a few mods, worked great for me with a Wusthof I recently picked up from ebay. Didn't take any before pics, but I'll take some after pics when I'm done restoring it.

I didn't remove the pins. I placed a plastic spacer between the scales to separate them to the distance I wanted, then ran it under my hot-water-on-demand, which is just a bit under boiling. I kept them there for about 10 seconds, then allowed them to cool, then repeated another two times. Turned out almost perfect.*

*The almost was the white film you mention above, and the reason for using distilled water. I'm going to try that next time. The film buffed out on the polishing wheel.

Mind you the warping wasn't as bad as what you show on that GE, so keeping it pinned worked fine for my needs. I could see how unpinning might be necessary with certain warping.