Yes a cut through is where you make a hole through the sand. It is always difficult to give sense of scale in a sand sculpture photo. Now I usually make sure a person is in the picture. The figures in the hole were a little smaller that life size.
There have been times when I have done quite dangerous stuff with sand but usually it is a calculated risk. But you just never know if the sand is going to fall until it's too late. The sand would for sure crush me if it fell but I lived to make another sculpture.
Danish sand in general is quite strong and is selected for this reason. If it did come down it would be more like blocks of soft clay.
Sometimes I am even surprised at how my sculptures stay up.
Thanks as always for you comments.