X
GLAN
C
I
N
G
(Hopefully this will render correctly) Anyway, suppose there were an obstacle cell in the 4th cell of row 8. Then if the entry at 27 goes horizontally it would glance off the cell at row 7 column 3 and head north in the 3rd column.
If the obstacle were in row 7, however, 27 could not go horizontally since it would run head on into that cell and have to stop since there is no second number.
25 middle is &lit - 'in the wings advancing' clues the two outside letters AG.