Just to clarify - nothing we have discussed is actually 'free castling'. In free castling, the king can choose which square and the rook also has a choice of which square. Hence my original response... For actual free castling, you need to record a third square and the ~ notation doesn't accomplish that.
Just to clarify - nothing we have discussed is actually 'free castling'. In free castling, the king can choose which square and the rook also has a choice of which square. Hence my original response... For actual free castling, you need to record a third square and the ~ notation doesn't accomplish that.