Irons

A sailing boat is in Irons when it is pointing too close to the wind to catch the sail, and with no speed, you cannot use the rudder to turn away from the wind.
What I learnt on Sunday is that even if you are not sailing forward, you my be sailing backwards, and so using the rudder may be of use, but you have to turn it the "wrong" way.  If you attempt to steer away from the wind, all you manage to do is turn towards it.  To the extent you are sailing backwards, you can turn the rudder towards where you want to stern to go.
In open water, you are not particularly worried as to which direction you point, provided you do not turn back towards the wind by not recognising the rudder works in reverse.  You can always sail backwards intentionally, by holding the boom out to the side, but it is worth knowing that you may be sailing backwards even without holding the boom.
If I had realised that, and had my wits about me, I might have remembered a simpler way of getting out of irons. That is raising the centre-board. Instead of pivoting about the centreboard, you start pivoting about the rudder.
Finally there is the solution that was not available to me, as I was sailing with a single sail.  You can tighten the jib, so that it catches the wind a turn the nose away from the wind