I am confused by this whole controversy. As I understand it, the
issue is, artificial horizons would enable a pilot to cheat by flying
in clouds, and there's no way to detect it, so they must be banned.
However, even without an artificial horizon, a pilot can still fly say
100ft below cloud base, which is also against regulations and cannot
be detected. So, the only way really make sure nobody is cheating is
to ban contest flying on days when there are clouds expected. Problem
solved!