Don't know about the thread (I've only scanned it) but the last version of the report I read said that yes, ice* blockage in the heat exchanger can cause the symptoms seen. However, it went on to say that the timing of things observed at the engine would tend to put the blockage some 20 feet farther up the fuel line, and they are at a complete loss currently as to how that can happen - they can't find a point 20 feet back that can feasibly be blocked by ice.
I think the summary (of the report, not necessarily this thread) is: did ice* blockage cause the problem? Yes. Was it in the heat exchanger? Don't know. Was it farther back? Maybe, but don't see how that could happen. More research is required, and more research is happening.
* The report goes to some lengths to note that the "ice" is NOT 100% water. It is a frozen slush of water and fuel, and the water makes up a fairly small percentage of the slush.