Step 1

Set up in ho stack, disc is in or near centre of field. Initiate from 1

Step 2

1 Slashes across field. 3 and 4 clear deep. 2 waits for continuation

Step 3

2 has all the field to work with to get open. 4 is waiting for continuation

Step 4

4 has all the field to get open.

Step 5