Silverstrata,
Another problem identified from this thread, is the poor understanding of systems and procedures by some pilots (presuming they fly) - not even understanding capture modes, for instance.
It is not poor understanding of the systems, it is poorly written manuals. When I can't find any information about how the altitude capture logic works when in WS, then I have to rely on my experience from the simulator. de facto says, since it is not written that the FD/AP will capture the altitude, it will not.
Why the AP have to disconnect when you do a single channel approach is a question I have yet to get an answer to. It's a stone age technology, and the reason for several near accidents. You can blame pilots handling skills, but I know what I would prefer when I am dead tired in crappy weather.