Olympus Zuiko 17mm vs Panasonic Lumix 20mm

You are right that the E-M5 & 7-14 combo has problems with purple-colored flare/reflections. This, however, has nothing to do with either LaCA or LoCA. Look at the latest posts in the thread you linked to for some ideas of what's actually going on.

The problems with the 12-35 discussed on the forum, by contrast, are about LaCA and LoCA, and I think it is well established by now that the lens has a bit of both. With regard to LoCA, I should point out that I am talking about in-focus LoCA (purple fringing). Just about every lens will show some OOF LoCA but that's not what I have in mind here.

The LoCA pattern shown by the 12-35 is typical of many Pany WAs (WA primes as well as zooms with a WA end). It usually manifests itself primarily as a one-sided purple fringe (after LaCA has been corrected), appearing on the inside (center side) of for example branches or dark leaves against a white sky. The phenomenon is virtually absent in the center but gets progressively worse towards the corners. There is an very good illustration provided by ginsbu here:

http://forums.dpreview.com/forums/post/50176940

Many otherwise excellent Pany lenses have at least some of it, e.g., the 7-14/4, the 14-45/3.5-5.6, the 14/2.5, and the 20/1.7 (I have them all).